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51.
Addolorata Corrado Ripalta Colia Angiola Mele Valeria Di Bello Antonello Trotta Anna Neve Francesco Paolo Cantatore 《PloS one》2015,10(9)
A reduced bone mineral density (BMD) is observed in several rheumatic autoimmune diseases, including Systemic Sclerosis (SSc); nevertheless, data concerning the possible determinants of bone loss in this disease are not fully investigated. The aim of this study is to evaluate the relationship between BMD, body mass composition, skin sclerosis and serum Vitamin D levels in two subsets of SSc patients. 64 post-menopausal SSc patients, classified as limited cutaneous (lcSSc) or diffuse cutaneous (dcSSc) SSc, were studied. As control, 35 healthy post-menopausal women were recruited. Clinical parameters were evaluated, including the extent of skin involvement. BMD at lumbar spine, hip, femoral neck and body mass composition were determined by dual-energy X-ray absorptiometry. Serum calcium, phosphorus, alkaline phosphatase, urine pyridinium cross-links, intact parathyroid hormone and 25-hydroxyvitamin D (25OHD) were measured. BMD at spine, femoral neck and total hip was significantly lower in SSc patients compared to controls. In dcSSc subset, BMD at spine, femoral neck and total hip was significantly lower compared to lcSSc. No differences in both fat and lean mass were found in the three study groups even if patients with dcSSc showed a slightly lower total body mass compared to healthy controls. Total mineral content was significantly reduced in dSSc compared to both healthy subjects and lcSSc group. Hypovitaminosis D was observed both in healthy post-menopausal women and in SSc patients, but 25OHD levels were significantly lower in dcSSc compared to lcSSc and inversely correlated with the extent of skin thickness. These results support the hypothesis that the extent of skin involvement in SSc patients could be an important factor in determining low circulating levels of 25OHD, which in turn could play a significant role in the reduction of BMD and total mineral content. 相似文献
52.
An integrated assessment of histopathological changes of the enteric neuromuscular compartment in experimental colitis
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Chiara Ippolito Cristina Segnani Mariella Errede Daniela Virgintino Rocchina Colucci Matteo Fornai Luca Antonioli Corrado Blandizzi Amelio Dolfi Nunzia Bernardini 《Journal of cellular and molecular medicine》2015,19(2):485-500
Bowel inflammatory fibrosis has been largely investigated, but an integrated assessment of remodelling in inflamed colon is lacking. This study evaluated tissue and cellular changes occurring in colonic wall upon induction of colitis, with a focus on neuromuscular compartment. Colitis was elicited in rats by 2,4‐dinitrobenzenesulfonic acid (DNBS). After 6 and 21 days, the following parameters were assessed on paraffin sections from colonic samples: tissue injury and inflammatory infiltration by histology; collagen and elastic fibres by histochemistry; HuC/D, glial fibrillar acidic protein (GFAP), proliferating cell nuclear antigen (PCNA), nestin, substance P (SP), von Willebrand factor, c‐Kit and transmembrane 16A/Anoctamin1 (TMEM16A/ANO1) by immunohistochemistry. TMEM16A/ANO1 was also examined in isolated colonic smooth muscle cells (ICSMCs). On day 6, inflammatory alterations and fibrosis were present in DNBS‐treated rats; colonic wall thickening and fibrotic remodelling were evident on day 21. Colitis was associated with both an increase in collagen fibres and a decrease in elastic fibres. Moreover, the neuromuscular compartment of inflamed colon displayed a significant decrease in neuron density and increase in GFAP/PCNA‐positive glia of myenteric ganglia, enhanced expression of neural SP, blood vessel remodelling, reduced c‐Kit‐ and TMEM16A/ANO1‐positive interstitial cells of Cajal (ICCs), as well as an increase in TMEM16A/ANO1 expression in muscle tissues and ICSMCs. The present findings provide an integrated view of the inflammatory and fibrotic processes occurring in the colonic neuromuscular compartment of rats with DNBS‐induced colitis. These morphological alterations may represent a suitable basis for understanding early pathophysiological events related to bowel inflammatory fibrosis. 相似文献
53.
54.
Immunostaining for nucleophosmin in bone marrow trephine biopsy specimens in acute myeloid leukemias
55.
Rodríguez-Argüelles MC Mosquera-Vázquez S Tourón-Touceda P Sanmartín-Matalobos J García-Deibe AM Belicchi-Ferrari M Pelosi G Pelizzi C Zani F 《Journal of inorganic biochemistry》2007,101(1):138-147
Cobalt(II), nickel(II), copper(II) and zinc(II) complexes of 2-thiophenecarbonyl and isonicotinoyl hydrazones of 3-(N-methyl)isatin (HL(1) and HL(2), respectively) were synthesized and characterized, being the crystal structures of HL(1), HL(2) and [Ni(L(1))(2)].2CHCl(3) elucidated by X-ray diffraction techniques. The in vitro antimicrobial activity of all these compounds was tested against several bacteria and fungi. HL(1)and its complexes exhibited a strong inhibition of the growth of Haemophilus influenzae (MIC 0.15-1.50microg/mL) and good antibacterial properties towards Bacillus subtilis (MIC 3-25microg/mL). The minimal inhibitory concentration (MIC) was defined as the lowest concentration of compound inhibiting the growth of each strain. The antibacterial effectiveness was confirmed against a number of Gram positive bacteria, including methicillin-resistant Staphylococcus aureus. Yeasts and moulds showed a low susceptibility, except the dermatophyte mould Epidermophyton floccosum that is inhibited at concentrations ranging from 6 to 50microg/mL. In general, the antimicrobial activity of the thiophene derivatives was greater than that of the isonicotinic analogues. 相似文献
56.
de Tombe PP Belus A Piroddi N Scellini B Walker JS Martin AF Tesi C Poggesi C 《American journal of physiology. Regulatory, integrative and comparative physiology》2007,292(3):R1129-R1136
We employed single myofibril techniques to test whether the presence of slow skeletal troponin-I (ssTnI) is sufficient to induce increased myofilament calcium sensitivity (EC(50)) and whether modulation of EC(50) affects the dynamics of force development. Studies were performed using rabbit psoas myofibrils activated by rapid solution switch and in which Tn was partially replaced for either recombinant cardiac Tn(cTn) or Tn composed of recombinant cTn-T (cTnT) and cTn-C (cTnC), and recombinant ssTnI (ssTnI-chimera Tn). Tn exchange was performed in rigor solution (0.5 mg/ml Tn; 20 degrees C; 2 h) and confirmed by SDS-PAGE. cTnI exchange induced a decrease in EC(50); ssTnI-chimera Tn exchange induced a further decrease in EC(50) (in microM: endogenous Tn, 1.35 +/- 0.08; cTnI, 1.04 +/- 0.13; ssTnI-chimera Tn, 0.47 +/- 0.03). EC(50) was also decreased by application of 100 microM bepridil (control: 2.04 +/- 0.03 microM; bepridil 1.35 +/- 0.03 microM). Maximum tension was not different between any groups. Despite marked alterations in EC(50), none of the dynamic activation-relaxation parameters were affected under any condition. Our results show that 1) incorporation of ssTnI into the fast skeletal sarcomere is sufficient to induce increased myofilament Ca(2+) sensitivity, and 2) the dynamics of actin-myosin interaction do not correlate with EC(50). This result suggests that intrinsic cross-bridge cycling rate is not altered by the dynamics of thin-filament activation. 相似文献
57.
Emiliano Ukmar Corrado Battisti Luca Luiselli Marco A. Bologna 《Biodiversity and Conservation》2007,16(12):3287-3300
Breeding bird communities in burnt and unburnt residual pinewoods were studied over 3 years by line-transect method, following
a catastrophic fire event in Castelfusano (Rome, Central Italy; July 2000). We applied bootstrap procedures to evaluate whether
the observed data were true or just produced by chance, and then examined the emerging patterns at three levels: community,
guild and species levels. At the community level, fire acted on breeding bird communities by altering especially the total
abundance patterns: the species abundance decreased in the burnt pinewood compared to the residual one, but other parameters
were not significantly affected by fire. As a consequence of fire, the destruction and structural simplification of the canopy
and shrubby component, as well as the increase of edge habitat and patchiness at landscape scale, induced a turnover in species
between pinewoods. Species turnover was higher at the burnt than at the residual pinewoods, during all the 3 years of study.
At the guild level, the forest species decreased strongly in terms of richness and abundance in the burnt pinewoods, contrary
to the edge and open habitat species which increased in terms of richness, abundance and evenness. Edge species showed the
highest turnover in burnt pinewood during the whole period of study. At species level, after an a priori subdivision (based
on bibliographic search) of the various species in two ecological guilds (forest versus edge species), it was found that an
a posteriori statistical analysis confirmed the expected trend, i.e. that the species which decreased significantly in burnt
pinewood were essentially the forest species, whereas the species which increased were essentially the edge/open habitat ones.
Overall, in order to investigate the effects of fire catastrophes on birds, the guild approach seems more exhaustive than
the taxonomic community approach, where intrinsic confounding trends are present. 相似文献
58.
Damiano Porcelli Paolo Barsanti Graziano Pesole Corrado Caggese 《BMC evolutionary biology》2007,7(1):215
Background
When orthologous sequences from species distributed throughout an optimal range of divergence times are available, comparative genomics is a powerful tool to address problems such as the identification of the forces that shape gene structure during evolution, although the functional constraints involved may vary in different genes and lineages. 相似文献59.
Stefano Biffani Corrado Dimauro Nicolò Macciotta Attilio Rossoni Alessandra Stella Filippo Biscarini 《遗传、选种与进化》2015,47(1)
Background
SNP (single nucleotide polymorphisms) genotype data are increasingly available in cattle populations and, among other things, can be used to predict carriers of specific haplotypes. It is therefore convenient to have a practical statistical method for the accurate classification of individuals into carriers and non-carriers. In this paper, we present a procedure combining variable selection (i.e. the selection of predictive SNPs) and linear discriminant analysis for the identification of carriers of a haplotype on BTA19 (Bos taurus autosome 19) known to be associated with reduced cow fertility. A population of 3645 Brown Swiss cows and bulls genotyped with the 54K SNP-chip was available for the analysis.Results
The overall error rate for the prediction of haplotype carriers was on average very low (∼≤1%). The error rate was found to depend on the number of SNPs in the model and their density around the region of the haplotype on BTA19. The minimum set of SNPs to still achieve accurate predictions was 5, with a total test error rate of 1.59.Conclusions
The paper describes a procedure to accurately identify haplotype carriers from SNP genotypes in cattle populations. Very few misclassifications were observed, which indicates that this is a very reliable approach for potential applications in cattle breeding. 相似文献60.
Giuseppina Apicella Debora Beldì Giansilvio Marchioro Sara Torrente Sara Tunesi Corrado Magnani Alessandro Volpe Carlo Terrone Marco Krengli 《Reports of Practical Oncology and Radiotherapy》2015,20(2):113-122