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Bleavins K Perone P Naik M Rehman M Aslam MN Dame MK Meshinchi S Bhagavathula N Varani J 《Biological trace element research》2012,145(2):257-267
The purpose of this study was to assess insoluble salts containing gadolinium (Gd3+) for effects on human dermal fibroblasts. Responses to insoluble Gd3+ salts were compared to responses seen with Gd3+ solubilized with organic chelators, as in the Gd3+-based contrast agents (GBCAs) used for magnetic resonance imaging. Insoluble particles of either Gd3+ phosphate or Gd3+ carbonate rapidly attached to the fibroblast cell surface and stimulated proliferation. Growth was observed at Gd3+ concentrations between 12.5 and 125 μM, with toxicity at higher concentrations. Such a narrow window did not characterize
GBCA stimulation. Proliferation induced by insoluble Gd3+ salts was inhibited in the presence of antagonists of mitogen-activated protein kinase and phosphatidylinositol 3-kinase
signaling pathways (similar to chelated Gd3+) but was not blocked by an antibody to the platelet-derived growth factor receptor (different from chelated Gd3+). Finally, high concentrations of the insoluble Gd3+ salts failed to prevent fibroblast lysis under low-Ca2+ conditions, while similar concentrations of chelated Gd3+ were effective. In conclusion, while insoluble Gd3+ salts are capable of stimulating fibroblast proliferation, one should be cautious in assuming that GBCA dechelation must
occur in vivo to produce the profibrotic changes seen in association with GBCA exposure in the subset of renal failure patients
that develop nephrogenic systemic fibrosis. 相似文献
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Michael K. Dame Tejaswi Paruchuri Marissa DaSilva Narasimharao Bhagavathula William Ridder James Varani 《In vitro cellular & developmental biology. Animal》2009,45(9):551-557
Göttingen minipigs were treated topically for 6 d with a novel retinoid (MDI 301) at concentrations ranging from 0.3% to 30% in cream vehicle. Treatment of the minipigs did not adversely affect their health (hematological and necropsy parameters) or produce changes in the skin suggestive of retinoid-induced skin irritation. After killing the animals, skin samples from each treatment site were excised and maintained in organ culture for 6 d. In addition, untreated skin was also maintained in organ culture and treated with MDI 301 (0.1–5 μg/ml). After 3 d, the culture supernatants were collected and analyzed for levels of collagen type I and for matrix metalloproteinases (MMPs). Both skin samples treated in vivo and skin samples exposed to MDI 301 in culture demonstrated increased collagen production. Only slight changes in levels of MMP-2 (gelatinase A) or MMP-9 (gelatinase B) were seen. After 6 d, the organ-cultured skin was fixed in formalin and prepared for histology. The organ-cultured skin was compared to skin that was fixed at killing after in vivo treatment. Epidermal hyperplasia was quantified at various MDI 301 concentrations. In vivo and in vitro treatments showed similar results—although the thickness was not substantially changed on average, there were focal areas of hyperplasia at higher retinoid concentrations. Taken together, these data suggest that MDI 301 enhances collagen production in minipig skin, without irritation. Furthermore, these studies suggest that minipig skin exposed to the retinoid in organ culture is equally predictive as topically treated skin. The in vitro organ culture approach may provide a cost-effective alternative model to that of the intact animal for skin retinoid testing. 相似文献
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Narasimharao V. Marella Brandon Seifert Priyadharsini Nagarajan Satrajit Sinha Ronald Berezney 《Journal of cellular physiology》2009,221(1):139-146
Undifferentiated human epidermal keratinocytes are self‐renewing stem cells that can be induced to undergo a program of differentiation by varying the calcium chloride concentration in the culture media. We utilize this model of cell differentiation and a 3D chromosome painting technique to document significant changes in the radial arrangement, morphology, and interchromosomal associations between the gene poor chromosome 18 and the gene rich chromosome 19 territories at discrete stages during keratinocyte differentiation. We suggest that changes observed in chromosomal territorial organization provides an architectural basis for genomic function during cell differentiation and provide further support for a chromosome territory code that contributes to gene expression at the global level. J. Cell. Physiol. J. Cell. Physiol. 221: 139–146, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
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Muralidhar?Metta Sriramana?Kanginakudru Narasimharao?Gudiseva Javaregowda?NagarajuEmail author 《Genome biology》2004,5(4):P8
Molecular characterization of cattle breeds is important for the prevention of germplasm erosion by cross breeding. The present
study was carried out to characterize two Indian cattle breeds, Ongole and Deoni using microsatellite markers. Using 5 di-and
5 tri- nucleotide repeat loci, 17 Ongole and 13 Deoni unrelated individuals were studied. Of the ten loci, eight revealed
polymorphism in both the breeds. The di-nucleotide repeats loci were found to be more polymorphic (100%) than tri-nucleotide
repeat loci (60%). A total of 39 polymorphic alleles were obtained at 4.5 alleles per locus in Ongole and 4.1 in Deoni. The
average expected heterozygosity was 0.46 (+0.1) and 0.50 (+0.1) in Ongole and Deoni breeds, respectively. The PIC values of the polymorphic loci ranged from 0.15 to 0.79 in Ongole and
0.13 to 0.80 in Deoni breeds. Six Ongole specific and three Deoni specific alleles were identified. The two breeds showed
a moderate genetic relationship between themselves with a F
ST
value of 0.10. 相似文献
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Jenkins W Perone P Walker K Bhagavathula N Aslam MN DaSilva M Dame MK Varani J 《Biological trace element research》2011,144(1-3):621-635
The purpose of this study was to compare each of the 14 naturally occurring lanthanoid metal ions for ability to stimulate pro-fibrotic responses in human dermal fibroblasts. When fibroblasts were exposed to individual lanthanoids over the concentration range of 1-100?μM, increased proliferation was observed with each of the agents as compared with control cells that were already proliferating rapidly in a growth factor-enriched culture medium. Dose-response differences were observed among the individual metal ions. Matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 levels were also increased in response to lanthanoid exposure but type I procollagen production was not. A dose-response relationship between induction of proliferation and increased MMP-1 was observed. Non-lanthanoid transition metal ions (aluminum, copper, cobalt, iron, magnesium, manganese, nickel, and zinc) were examined in the same assays; there was little stimulation with any of these metals. When epidermal keratinocytes were examined in place of dermal fibroblasts, there was no growth stimulation with any of the lanthanoids. Several of the lanthanoid metals inhibited keratinocyte proliferation at higher concentrations (50-100?μM). 相似文献
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Michael K. Dame Narasimharao Bhagavathula Cohra Mankey Marissa DaSilva Tejaswi Paruchuri Muhammad Nadeem Aslam James Varani 《In vitro cellular & developmental biology. Animal》2010,46(2):114-122
Normal and neoplastic human colon tissue obtained at surgery was used to establish conditions for organ culture. Optimal conditions
included an atmosphere of 5% CO2 and 95% O2; tissue partially submerged with mucosa at the gas interface; and serum-free medium with 1.5 mM Ca2+ and a number of growth supplements. Histological, histochemical, and immunohistochemical features that distinguish normal
and neoplastic tissue were preserved over a 2-d period. With normal tissue, this included the presence of elongated crypts
with small, densely packed cells at the crypt base and mucin-containing goblet cells in the upper portion. Ki67 staining,
for proliferating cells, was confined to the lower third of the crypt, while expression of extracellular calcium-sensing receptor
was seen in the upper third and surface epithelium. E-cadherin and β-catenin were expressed throughout the epithelium and
confined to the cell surface. In tumor tissue, the same disorganized, abnormal glandular structures seen at time zero were
present after 2 d. The majority of cells in these structures were mucin-poor, but occasional goblet cells were seen and mucin
staining was present. Ki67 staining was seen throughout the abnormal epithelium and calcium-sensing receptor expression was
weak and variable. E-cadherin was seen at the cell surface (similar to normal tissue), but in some places, there was diffuse
cytoplasmic staining. Finally, intense cytoplasmic and nuclear β-catenin staining was observed in cultured neoplastic tissue. 相似文献
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Muralidhar?Metta Sriramana?Kanginakudru Narasimharao?Gudiseva Javaregowda?NagarajuEmail author 《BMC genetics》2004,5(1):16
Background
Molecular characterization of cattle breeds is important for the prevention of germplasm erosion by cross breeding. The Indian zebu cattle have their significant role in evolution of present day cattle breeds and development of some of the exotic breeds. Microsatellites are the best available molecular tools for characterization of cattle breeds. The present study was carried out to characterize two Indian cattle breeds, Ongole and Deoni, using microsatellite markers. 相似文献9.
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