bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adrenergic responses of rat colonic muscularis mucosae
Authors: Percy William H , Keupp Sarah M 
Published: July 2008

AbstractWe have investigated adrenoceptor-mediated responses of muscularis mucosae from the proximal, mid and distal regions of the rat colon. Noradrenaline-induced relaxations of the muscularis mucosae in each region were unaffected by atenolol, butoxamine or propranolol, but they were attenuated by the selective β3-adrenoceptor antagonist cyanopindolol. The β3-adrenoceptor agonist CL216343 elicited concentration-dependent relaxation of the muscularis mucosae in all regions of the colon. Isoprenaline, a non-selective β-adrenoceptor agonist, evoked concentration-dependent relaxations of the muscularis mucosae in all regions, but only in the proximal colon were these significantly larger than the maximum noradrenaline-induced relaxation. The α1-adrenoceptor agonist methoxamine caused large contractions of the proximal colonic muscularis mucosae. When proximal tissue was pretreated with phentolamine, an α1-adrenoceptor antagonist, maximal noradrenaline- and isoprenaline-induced relaxations did not differ significantly. Although the mid colonic muscularis mucosae was also found to possess excitatory α1-adrenoceptors, these were associated with small contractions and did not modify the muscle's inhibitory responses to noradrenaline. Distal colonic muscularis mucosae lacked excitatory adrenoceptors and only responded to noradrenaline with β3-adrenoceptor-mediated relaxations. No evidence was obtained for functional α2-adrenoceptors on the muscularis mucosae in any region of the rat colon. These data demonstrated that noradrenaline-induced relaxation of the rat colonic muscularis mucosae was mediated via β3-adrenoceptors throughout, but in the proximal region this was modified by concurrent excitatory α1-adrenoceptor activation. Based upon these observations it appeared unlikely that noradrenaline-induced relaxation of rat colonic muscularis mucosae would be functionally linked to the secretory responses of the corresponding mucosa during periods of increased sympathetic activity.
Inhibition of H+/K+ ATPase in the gastroprotective effect ofBaccharis illinitaDC
Authors: Freitas Cristina S , Baggio Cristiane H , Finau Jaqueline , Anginoni Margano , Pizzolatti Moacir G , Santos Adair R S , Marques Maria C A 
Published: July 2008

AbstractBaccharis illinita DC (Compositae) is used in folk medicine to treat gastric disturbances. Preliminary studies with other extracts of B. Illinita showed gastric protection against ethanol-, indometacin- and stress-induced ulcers and the inhibition of gastric secretion. Based on these data, the aim of this study was to verify the pathways involved in the inhibition of gastric secretion. The chloroform extract (CE) of flowers from B. illinita (3, 10, 30 and 100 mg kg−1 i.p.) tested on rats with pylorus ligature reduced the volume and the total acidity of gastric content by approximately 50% (ED50 = 69 mg kg−1). Treatment with CE (100 mg kg−1 i.p.) reduced the gastric total acidity stimulated by histamine, bethanechol and pentagastrin to 42%, 27% and 57% of that in the stimulated control group, respectively. The CE (10, 30 and 100 μM) inhibited H+/K+ ATPase activity in-vitro, with an IC50 of 37 μM. The isolated flavonoid luteolin (1, 3, 10 and 30 μM) also inhibited H+/K+ ATPase activity by 50%, at a dose of 30 μM. Our results suggest that the reduction in gastric secretion occurs through inhibition of H+/K+ ATPase, which is the final step in acid secretion and therefore one of the most important steps.
PCR-Based Analysis of Differentially Methylated Regions of GNAS Enables Convenient Diagnostic Testing of Pseudohypoparathyroidism Type Ib
Authors: Weinhaeusel Andreas , Thiele Susanne , Hofner Manuela , Hiort Olaf , Noehammer Christa 
Published: July 2008

Abstract
Background: Pseudohypoparathyroidism type Ib (PHPIb) is characterized by parathyroid hormone (PTH) resistance, which can lead to hypocalcemia, hyperphosphatemia, and increased serum PTH. The disorder is caused by mutations in regulatory regions of the GNAS gene (GNAS complex locus) that lead to interferences in the methylation status of alternative GNAS promoters, such as exon A/B, NESP55, and XLα-s. PHPIb comprises disorders that show distinctive changes in methylation status but share the same clinical phenotype: (a) loss of methylation only at exon A/B of the GNAS gene and involving no other obvious epigenetic abnormalities [e.g., those caused by heterozygous microdeletions in the STX16 (syntaxin 16) region and found in many patients with autosomal dominant (AD) PHPIb]; (b) methylation abnormalities at several differentially methylated regions (DMRs), which are observed in most patients with sporadic PHPIb and some families with AD PHPIb.
Methods: To permit early and reliable diagnosis of suspected PHPIb, we designed methylation-sensitive restriction enzyme–based and bisulfite deamination–based PCR tests for exon A/B and NESP55 DMRs.
Results: Both PCR strategies permit proper methylation testing of GNAS and NESP55 DMRs and elucidate different disease subtypes. We have identified a novel microsatellite repeat polymorphism within GNAS exon A/B, and pedigree analyses have shown its presence to be conclusive evidence for familial disease.
Conclusions: We provide a simple diagnostic test for PHPIb, an imprinting disorder caused by different molecular changes within the GNAS complex locus. PHPIb, a complex and diagnostically challenging clinical phenotype, can be treated successfully by taking steps before the manifestation of symptoms to avoid clinical complications in affected patients or asymptomatic members of affected families who show positive results in genetic tests.
Comparison between Immunoturbidimetry, Size-Exclusion Chromatography, and LC-MS to Quantify Urinary Albumin
Authors: Shaikh Aisha , Seegmiller Jesse C , Borland Timothy M , Burns Bradley E , Ladwig Paula M , Singh Ravinder J , Kumar Rajiv , Larson Timothy S , Lieske John C 
Published: July 2008

Abstract
Background: The accurate and precise measurement of urinary albumin is critical, since even minor increases are diagnostically sensitive indicators of renal disease, cardiovascular events, and risk for death. To gain insights into potential measurement biases, we systematically compared urine albumin measurements performed by LC-MS, a clinically available immunoturbidimetric assay, and size-exclusion HPLC.
Methods: We obtained unused clinical urine samples from 150 patients who were stratified by degrees of albuminuria (&lt;20 mg/L, 20–250 mg/L, &gt;250 mg/L) as determined by the immunoturbidimetric assay used in our clinical laboratory (Roche Hitachi 912). Urine albumin was then remeasured via LC-MS and HPLC (Accumin™) assays.
Results: The immunoturbidimetric assay, calibrated using manufacturer-supplied serum-derived calibrators (Diasorin), underestimated albumin compared with LC-MS. After calibration with purified HSA, this immunoturbidimetric assay correlated well with LC-MS. HPLC overestimated albumin compared with both LC-MS and immunoturbidimetry. The current LC-MS and HPLC assays both performed poorly at concentrations &lt;20 mg/L.
Conclusions: Efforts are needed to establish gold-standard traceable calibrators for clinical assays. LC-MS is a specific method to quantify albumin in native urine when concentrations exceed 20 mg/L, and therefore could be employed for standardization among assays.
Hydrogen-bonded frameworks in molecular metal-organic crystals: the network approach
Authors: Baburin Igor A. 
Published: July 2008

Abstract
Supramolecular architectures in molecular metal-organic crystals with three-dimensional networks of hydrogen bonds have been studied from the topological point of view. 636 hydrogen-bonded frameworks have been classified into 78 types of three-dimensional nets. It is shown that the resulting type of a framework is predetermined by prevailing octahedral coordination of metals in complexes that leads to the preference of 6-and 8-coordinated net topologies and those framework types compatible with the inversion symmetry of a complex. The study of molecular packings in metal-organic crystals with three-dimensional hydrogen-bonded frameworks and in those without hydrogen bonding has confirmed the trend to form close-packed motifs, irrespective of the presence of hydrogen bonds. Finally, a comparative analysis of organic and metal-organic hydrogen-bonded molecular frameworks as well as valence-bonded metal-organic frameworks is presented.
Ca2NaSiO4F: a new monoclinic polymorph
Authors: Krüger Hannes , Kahlenberg Volker 
Published: July 2008

Abstract
The crystal structure of a new monoclinic Ca2NaSiO4F polymorph was determined by single crystal X-ray diffraction methods. It crystallises in space group P21/c, unit cell parameters are a = 13.5385(8), b = 7.1338(4), c = 10.6689(6) Å and β = 113.231(4)°, with Z = 8. The crystals show twinning by pseudo merohedry. Monoclinic dicalcium sodium fluoride silicate is a superstructure of a previously known orthorhombic compound of the same composition. A re-investigation of the orthorhombic Ca2NaSiO4F revealed weak diffuse X-ray scattering, which shows a relation to the monoclinic superstructure. Furthermore, both compounds exhibit additional twinning by partial merohedry interrelated with a hexagonal pseudo symmetry. The sixfold pseudo symmetry originates from chains of face-sharing anion-centred coordination polyhedra of fluorine atoms, which are octahedrally coordinated by mixed Ca/Na sites. Main deviations from hexagonal symmetry are caused by the arrangement of the isolated silicate tetrahedra.
Na8.25Y1.25Si6O18 and its family of zwölfer ring silicates
Authors: Többens Daniel M. , Kahlenberg Volker , Kaindl Reinhard , Sartory Bernhard , Konzett Jürgen 
Published: July 2008

Abstract
The crystal structure of a sodium yttrium silicate with nominal composition Na9YSi6O18 was determined from laboratory X-ray powder diffraction. The actual composition of the crystals was found to be Y-enriched, and a corrected nominal composition of Na8.25Y1.25Si6O18 was established. The compound is cubic with space group Pa−3 and unit cell parameter of a = 15.120 Å. The structure consists of twelve-membered rings of corner-connected SiO4-tetrahedra, which are arranged around the 3-fold axes of the structure. It is isostructural with K4SrGe3O9 and Na4CaSi3O9. A profound disorder results from the absence of any stochiometric composition. The existence of a simultaneous occurrence of two different conformations of the rings relates to the various ordered and disordered cation positions in the structure. Micro-Raman spectra obtained from the polycrystalline material confirm the observed disorder. A model explaining the conformational variations appearing in this structure type was derived from a systematic comparison of isostructural compounds.
Investigation of anhydrous metal(II) nitrates. I. Syntheses and crystal structures of Mg(NO3)2, Co(NO3)2 and Ni(NO3)2, with a stereochemical discussion
Authors: Giester Gerald , Lengauer Christian L. , Wildner Manfred , Zemann Josef 
Published: July 2008

Abstract
Mg(NO3)2, Co(NO3)2 and Ni(NO3)2 were obtained as tiny crystals by dehydration of melts of the respective hydrates in the range 410–450 K. Structure determinations and refinements are based on single crystal X-ray data (CCD area detector) measured at 120–370 K. Crystal parameters at 120 K: Mg(NO3)2: R−3, a = 10.474(1), c = 38.782(4) Å, Z = 36, R
1 = 0.028; Co(NO3)2: R−3, a = 10.445(1), c = 12.769(2) Å, Z = 12, R
1 = 0.019; Ni(NO3)2: R−3, a = 10.332(1), c = 12.658(2) Å, Z = 12, R
1 = 0.025. Co(NO3)2 and Ni(NO3)2 are isotypic; the structure of Mg(NO3)2 is closely related, although it is not simply a stacking variant – it forms a new structure type. In all three compounds the MO6 octahedra share all corners with the NO3 groups to form framework structures; any edge sharing is thereby avoided. The geometries of the structures are also discussed in relation to a simple theoretical cubic structure (space group Pa−3) with the same connection pattern of the MO6 and NO3 building units. Neither X-ray single crystal and powder work nor differential thermoanalytical investigations indicated polymorphism in the temperature range investigated.
Crystal structure and thermal analysis of new mononuclear nickel (II) complexes with NNN type pyrazolyl ligands and halids
Authors: Taştekin Mustafa , Durmuş Sefa , Şahin Ertan , Arici Cengiz , Emregül Kaan Cebesoy , Atakol Orhan 
Published: July 2008

Abstract
Mononuclear Ni(II) complexes of Bis-2,6(pyrazolyl)pyridine(pp), 2(1-pyrazolyl)-6-(3,5-dimethylpyrazol-1-yl)pyridine(mpp) and bis-2,6(3,5-dimethyl-pyrazolyl-1yl)pyridine(dmpp) were prepared in MeOH : H2O mixtures. The complexes were characterized using elemental analysis, IR spectroscopy, X-ray diffraction and thermal analysis. The molecular structure of [Nidmpp(H2O)2Br]Br was evaluated and the Ni(II) ion was found to be in a distorted octahedral coordination environment. One of the halogen ions was found to coordinate the Ni(II) ion whereas the other ion does not coordinate and forms hydrogen bonds with the water molecules situated on the neighboring complex molecules, resulting in a supramolecular arrangement. Thermogravimetric results showed three coordinated water molecules in the pp and mpp complexes. Conductometric and potentiometric studies of the complexes showed 2 and 1 turning points, respectively.
IFATS Collection: Using Human Adipose-Derived Stem/Stromal Cells for the Production of New Skin Substitutes
Authors: Trottier Valérie , Marceau-Fortier Guillaume , Germain Lucie , Vincent Caroline , Fradette Julie 
Published: July 2008

Abstract
The ability to harvest and culture stem cell populations from various human postnatal tissues is central to regenerative medicine applications, including tissue engineering. The discovery of multipotent mesenchymal stem cells within the stromal fraction of adipose tissue prompted their use for the healing and reconstruction of many tissues. Here, we examined the influence of adipose-derived stem/stromal cells (ASCs) on skin's regenerative processes, from a tissue engineering perspective. Using a self-assembly approach, human skin substitutes were produced. They featured a stromal compartment containing human extracellular matrix endogenously produced from either dermal fibroblasts or adipose-derived stem/stromal cells differentiated or not toward the adipogenic lineage. Human keratinocytes were seeded on each stroma and cultured at the air-liquid interface to reconstruct a bilayered skin substitute. These new skin substitutes, containing an epidermis and a distinctive stroma devoid of synthetic biomaterial, displayed characteristics similar to human skin. The influence of the type of stromal compartment on epidermal morphogenesis was assessed by the evaluation of tissue histology, the expression of key protein markers of the epidermal differentiation program (keratin [K] 14, K10, transglutaminase), the expression of dermo-epidermal junction components (laminins, collagen VII), and the presence of basement membrane and hemidesmosomes. Our findings suggest that adipose-derived stem/stromal cells could usefully substitute dermal fibroblasts for skin reconstruction using the self-assembly method. Finally, by exploiting the adipogenic potential of ASCs, we also produced a more complete trilayered skin substitute consisting of the epidermis, the dermis, and the adipocyte-containing hypodermis, the skin's deepest layer.
Disclosure of potential conflicts of interest is found at the end of this article.
In Vivo Osteoprogenitor Potency of Human Stromal Cells from Different Tissues Does Not Correlate with Expression of POU5F1 or Its Pseudogenes
Authors: Kaltz Nikolas , Funari Alessia , Hippauf Sandra , Delorme Bruno , Noël Danièle , Riminucci Mara , Jacobs Volker R. , Häupl Thomas , Jorgensen Christian , Charbord Pierre , Peschel Christian , Bianco Paolo , Oostendorp Robert A.J. 
Published: July 2008

Abstract
Expression of “stemness” markers is widely used as a predictor of stem cell properties of mesenchymal stem cells (MSC). Here, we show that bone marrow-derived (BM)-MSC show stem cell-like behavior in vivo; that is, they form ossicles with formation of bone, formation of adipocytes, and establishment of the murine hematopoietic microenvironment. Multipotent umbilical vein-derived stromal cells (UVSC), on the other hand, do not form bone, nor do they give rise to adipocytes in vivo. Despite these differences in stem-cell-like behavior, BM-MSC and UVSC express the two transcripts variants of POU5F1 at a similar level. Also, we found that in BM-MSC and UVSC, POU5F1 is detectable. However, more than 89% of the POU5F1 transcripts correspond to the POU5F1P1, -P3, or -P4 pseudogene. Despite low-level expression of POU5F1, we were unable to precipitate POU5F1 protein in either BM-MSC or UVSC. These results demonstrate that MSC stemness does not correlate to expression of POU5F1 transcripts or its pseudogenes.
Disclosure of potential conflicts of interest is found at the end of this article.
A Reservoir of Brown Adipocyte Progenitors in Human Skeletal Muscle
Authors: Crisan Mihaela , Casteilla Louis , Lehr Lorenz , Carmona Mamen , Paoloni-Giacobino Ariane , Yap Solomon , Sun Bin , Léger Bertrand , Logar Alison , Pénicaud Luc , Schrauwen Patrick , Cameron-Smith David , Russell Aaron Paul , Péault Bruno , Giacobino Jean-Paul 
Published: July 2008

Abstract
Brown adipose tissue uncoupling protein-1 (UCP1) plays a major role in the control of energy balance in rodents. It has long been thought, however, that there is no physiologically relevant UCP1 expression in adult humans. In this study we show, using an original approach consisting of sorting cells from various tissues and differentiating them in an adipogenic medium, that a stationary population of skeletal muscle cells expressing the CD34 surface protein can differentiate in vitro into genuine brown adipocytes with a high level of UCP1 expression and uncoupled respiration. These cells can be expanded in culture, and their UCP1 mRNA expression is strongly increased by cell-permeating cAMP derivatives and a peroxisome-proliferator-activated receptor-γ (PPARγ) agonist. Furthermore, UCP1 mRNA was detected in the skeletal muscle of adult humans, and its expression was increased in vivo by PPARγ agonist treatment. All the studies concerning UCP1 expression in adult humans have until now been focused on the white adipose tissue. Here we show for the first time the existence in human skeletal muscle and the prospective isolation of progenitor cells with a high potential for UCP1 expression. The discovery of this reservoir generates a new hope of treating obesity by acting on energy dissipation.
Disclosure of potential conflicts of interest is found at the end of this article.
Pheochromocytoma: Current Approaches and Future Directions
Authors: Adler Joel T. , Meyer-Rochow Goswin Y. , Chen Herbert , Benn Diana E. , Robinson Bruce G. , Sippel Rebecca S. , Sidhu Stan B. 
Published: July 2008

AbstractLearning ObjectivesAfter completing this course, the reader should be able to: Use current practice methods in the diagnosis of pheochromocytomas.Employ current practice methods in the treatment of pheochromocytomas.Evaluate the current molecular research that contributes to the treatment of pheochromocytomas.CME This article is available for continuing medical education credit at CME.TheOncologist.comPheochromocytomas are rare catecholamine-secreting tumors that arise from chromaffin tissue within the adrenal medulla and extra-adrenal sites. Because of the excess secretion of hormones, these tumors often cause debilitating symptoms and a poor quality of life. While medical management plays a significant role in the treatment of pheochromocytoma patients, surgical excision remains the only cure. Improved medical management and surgical techniques and an increased understanding of hereditary disease have improved the outcome of pheochromocytoma patients with benign disease; however, the outcome of patients with malignant disease remains poor. In this review, we discuss the presentation, diagnosis, management, and future directions in the management of this disease.
Effects, uptake, and fate of 2,4,6-trinitrotoluene aged in soil in plants and worms
Authors: Best Elly P. H , Tatem Henry E , Geter Kaaren N , Wells Melissa L , Lane Brian K 
Published: July 2008

AbstractThe present study was aimed at providing data to be used at predicting exposure-based effects of 2,4,6-trinitrotoluene (TNT) aged in soil on endpoint organisms representing two trophic levels. These data can be used to define criteria or reference values for environmental management and conducting specific risk assessment. Long-term exposure tests were conducted to evaluate sublethal toxicity and uptake of aged soil-based explosives, with TNT as the main contaminant. In these tests, plants were exposed for 55 d, and biomass and explosives residues were determined. Worms were exposed for 28 and 42 d, and biomass, number, and tissue residues were determined. Biomass of Lolium perenne significantly decreased with soil–TNT concentration, and an effective concentration causing a 20% decrease in biomass (EC20) for TNT metabolites of 3.75 mg/kg was calculated. The concentrations of TNT metabolites in shoots and roots were significantly related to concentrations in soil, as were concentrations of hexahydro-1,3,5-trinitro-1,3,5 triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7- tetrazocine (HMX). The mean bioconcentration factors, indicating the potential of a chemical to accumulate in an organism, were 0.9 for TNT metabolites, 71.8 for RDX, and 12.2 for HMX in L. perenne shoots. Biomass of Eisenia fetida adults significantly decreased with soil–TNT concentration, and an EC20 for TNT of 3.70 mg/kg was calculated. The TNT, RDX, and HMX levels in E. fetida were below detection.
Effects of post-Hurricane Katrina New Orleans (LA, USA) sediments on early development of the Japanese medaka (Oryzias latipes)
Authors: Liebl Andrea L , Granados Lisa H , Zhang Qiang , Wang Guangdi , Mielke Howard W , Gonzales Christopher R , Ennis Don G , Rees Bernard B 
Published: July 2008

Abstract
When Hurricane Katrina struck the U.S. Gulf Coast, levees surrounding New Orleans, Louisiana, USA, were breached, leading to widespread flooding of the city and potential contamination from industrial spills, residential sources, and redistribution of pre-existing pollutants. We chemically characterized sediment samples from five New Orleans locations and used early development and mutagenesis in Japanese medaka (Oryzias latipes) as metrics of the toxic effects of these sediments. Sediment samples were analyzed for organohalogen pesticides, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and metals. One month after Hurricane Katrina, four of the five sites had unsafe concentrations of arsenic and one or more pesticides, pesticide metabolites, or polycyclic aromatic hydrocarbons. Medaka embryonic mortality and time to hatching both increased during exposure to aqueous extracts of sediments, with the greatest toxicity observed for the most heavily contaminated sediment. Exposure to sediment extracts did not, however, result in significantly elevated rates of mutagenesis. When the most contaminated site was resampled 4.5 months later, the sediment had lower contaminant concentrations and fewer deleterious effects on medaka development. Using the medaka bioassay, therefore, we demonstrate toxic effects of post-Hurricane Katrina sediments immediately following the storm, with some amelioration over time of contaminant concentrations and their negative biological effects.