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11.
12.
Peter Schmidt Christa Kühn Jean-Charles Maillard Christian Pitra Ute Tiemann Rosemarie Weikard Manfred Schwerin 《Journal of interferon & cytokine research》2002,22(9):923-934
This study aimed to identify interferon-gamma (IFN-gamma) gene variants in cattle for diagnostic purposes. Therefore, the entire bovine IFN-gamma gene (BoIFNG) and 2605 bp of its promoter DNA were sequenced. The BoIFNG DNA sequence conforms to the published part of Bo-IFN-gamma cDNA. Primer extension experiments show the presence of a 5' extension of exon 1 by 42 nucleotides (nt). One SINE element (Bov-A2) is located in the 5'-region, and two SINE elements (Bov-tA, Bov-B) are contained in the 3'-region of BoIFNG. The variants were detected by comparative sequence analysis of PCR amplicons from different bovine species. Four polymorphic mononucleotide repeats are situated in the promoter and in intron 1. Four distinct series of single nucleotide polymorphisms (SNP) were found in functionally important regions of BoIFNG. The region between the two intron 1 microsatellites contains the highest density of SNPs in Bos taurus breeds. One G-T transversion in the coding region of exon 1 causes a Gly(14) to Val(14) exchange in the BoIFNG signal peptide of different bovine species. A G-A transition in exon 2 encodes a Ser(19) to Asn(19) change in the mature protein of the Tibetan yak. Genotyping of randomly sampled Holstein Friesian cows at selected SNPs and of both intron 1 microsatellites revealed two dominant BoIFNG microhaplotypes. The detected SNPs improve the recently reported genotyping system of cattle. 相似文献
13.
Lee YJ Hohoff C Domschke K Sand P Kuhlenbäumer G Schirmacher A Freitag CM Meyer J Stöber G Franke P Nöthen MM Fritze J Fimmers R Garritsen HS Stögbauer F Deckert J 《Neuroscience letters》2005,377(1):40-43
Several biochemical and pharmacological studies suggest that the catecholaminergic system involving the norepinephrine transporter (NET) is relevant for the pathogenesis of panic disorder. Three single nucleotide polymorphisms in the promoter or untranslated 5' region of the NET gene were investigated by means of RFLP analysis in a sample of 115 German patients with panic disorder and 115 matched controls. Statistical analysis failed to show association with the overall diagnosis of panic disorder. In the subgroup of patients with panic disorder without agoraphobia, however, two polymorphisms were found to be associated with the disease (G/C (rs2397771): p < 0.05; T/C (rs2242446): p < 0.01). While our data do not support a major function of the NET gene in the development of panic disorder, it may play a role in the subgroup of panic disorder without agoraphobia. 相似文献
14.
Andrew Wong Christa Lese Martin Konstantina Heretis Teresa Ruffalo Kim Wilber Walter King David H Ledbetter 《Genetics in medicine》2005,7(4):264-271
PURPOSE: Genome-wide telomere screening by fluorescence in situ hybridization (FISH) has revealed that approximately 6% of unexplained mental retardation is due to submicroscopic telomere imbalances. However, the use of FISH for telomere screening is labor intensive and time consuming, given that 41 telomeres are interrogated. We have evaluated the use of array-based Comparative Genomic Hybridization (aCGH) as a more efficient tool for identifying telomere rearrangements. METHODS: In this study, 102 individuals with unexplained mental retardation, with either normal or abnormal FISH results, were selected for a blinded retrospective study using aCGH. Results between the two methodologies were compared to ascertain the ability of aCGH to be used in a clinical diagnostics setting. RESULTS: We detected 100% of all imbalances previously identified by FISH (n = 17) and identified two additional abnormalities, a 10q telomere duplication and an interstitial duplication of 22q11. Interphase FISH analysis verified all abnormal array results. We also demonstrated that aCGH can accurately calibrate the size of telomere imbalances by using an array with "molecular rulers" for the telomeric regions of 1p, 16p, 17p, and 22q. CONCLUSION: This study demonstrates that aCGH is an equivalent methodology to telomere FISH for detecting submicroscopic deletions. In addition, small duplications that are not easily visible by FISH can be accurately detected using aCGH. Because aCGH allows simultaneous interrogation of hundreds to thousands of DNA probes and is more amenable to automation, it offers an efficient and high-throughput alternative for detecting and calibrating unbalanced rearrangements, both of the telomere region, as well as other genomic locations. 相似文献
15.
Keratinocyte growth factor is an important endogenous mediator of hair follicle growth, development, and differentiation. Normalization of the nu/nu follicular differentiation defect and amelioration of chemotherapy-induced alopecia. 总被引:8,自引:5,他引:8 下载免费PDF全文
D. M. Danilenko B. D. Ring D. Yanagihara W. Benson B. Wiemann C. O. Starnes G. F. Pierce 《The American journal of pathology》1995,147(1):145-154
The growth and development of hair follicles is influenced by a number of different growth factors and cytokines, particularly members of the fibroblast growth factor (FGF) family. Keratinocyte growth factor (KGF or FGF-7) is a recently identified 28-kd member of the FGF family that induces proliferation of a wide variety of epithelial cells, including keratinocytes within the epidermis and dermal adnexa. Because KGF induces marked proliferation of keratinocytes, and both KGF and KGF receptor (KGFR) mRNA are expressed at high levels in skin, we sought to localize KGF and KGFR in skin by in situ hybridization. KGFR mRNA was relatively strongly expressed by keratinocytes in the basilar epidermis as well as throughout developing hair follicles of rat embryos and neonates. KGF mRNA was expressed at lower levels than was KGFR but could be localized to follicular dermal papillae in rat embryos and neonates. These results prompted us to investigate the effects of KGF on hair follicles in two distinct murine models of alopecia. In the first model, recombinant KGF (rKGF) induced dose-dependent hair growth over most of the body in nu/nu athymic nude mice when administered intraperitoneally or subcutaneously over 17 to 18 days. When administered subcutaneously, rKGF induced the most extensive hair growth at the sites of injection. Histologically, rKGF induced marked follicular and sebaceous gland hypertrophy, a normalization of the nu/nu follicular keratinization defect, and an increase in follicular keratinocyte proliferation as assessed by bromodeoxyuridine labeling. In the second model, a neonatal rat model of cytosine arabinoside chemotherapy-induced alopecia in which interleukin-1, epidermal growth factor, and acidic FGF have all demonstrated some degree of alopecia cytoprotection, rKGF induced a dose-dependent cytoprotective effect, abrogating as much as 50% of the alopecia in this model when administered beginning 1 day before the onset of chemotherapy. Taken together, these data suggest that KGF is an important endogenous mediator of normal hair follicle growth, development, and differentiation. 相似文献
16.
The peptide melittin, the main constituent of bee venom is a potent stimulus for the generation of an eosinophil chemotactic factor (ECF) from human polymorphonuclear neutrophils, rat mast cells and rat peritoneal cells depleted in mast cells. Optimal EFC induction required a sublytic activation of the cells. With each cell type the kinetics of ECF generation were similar in that after an early rise in activity a steep fall off occurred at later times of incubation suggesting a mechanism of inactivation. The induction of ECF by melittin is increased in the presence of calcium. The polar portion of the melittin molecule (aminoacids 20–26) is responsible for the generation of the chemotactic activity. Other peptides of honey bee venom such as the mast cell degranulating peptide (MCD) or apamine do not initiate ECF release. It appears that melittin leads to ECF induction via the phospholipase A2-arachidonic acid dependent pathway of cell activation. Our data suggests that the lipid mediator ECF can be obtained from phagocytes and mast cells thus indicating the interdependence of inflammatory reactions. 相似文献
17.
Hocher B Dembowski C Slowinski T Friese ST Schwarz A Siren AL Neumayer HH Thöne-Reineke C Bauer C Nafz B Ehrenreich H 《Journal of molecular medicine (Berlin, Germany)》2001,78(11):633-641
The renal endothelin (ET) system, particularly the ET type B receptor, has been implicated in the regulation of sodium excretion and glomerular filtration rate (GFR). We analyzed kidney morphology and function in a rat strain characterized by complete absence of a functional ETB receptor. Due to Hirschsprung's disease limiting lifetime in these rats, studies were performed in 23-day-old rats. Kidney size and morphology (glomerular and interstitial matrix content, glomerular size and cell density and intrarenal vascular morphology) were normal in ETB-deficient rats. There were also no evidence of altered kidney cell cycle regulation in these rats. GFR was significantly lower, by 72% (P<0.001), in homozygous ETB-deficient rats than in wild-type rats. Fractional sodium excretion was likewise markedly reduced by 84% in homozygous ETB-deficient rats (P<0.001 versus wild-type rats). Treatment with the specific epithelial sodium channel blocker amiloride led to a much higher increase in fractional sodium excretion in ETB-deficient rats (934.2+/-73% in ETB-deficient rats versus 297+/-20% in wild-type rats, expressed as percentage of corresponding placebo treated control; P<0.001). Mean arterial blood pressure was elevated by 7.9 mmHg in homozygous ETB-deficient rats (P<0.05 versus wild-type rats). Our study demonstrates that ETB-deficiency causes early onset kidney dysfunction characterized by a markedly reduced sodium excretion, decreased GFR, and slightly elevated blood pressure. The complete absence of the ETB receptor causes in the kidney--in contrast to the colon--a functional rather than a developmental, neural crest cell dependent disease, since kidney morphology was normal in ETB-deficient rats. The much higher increase in the fractional sodium excretion in ETB-deficient rats after pharmacological blockade of the epithelial sodium channel indicates that the decreased fractional sodium excretion in ETB-deficient rats is most probably due to a lack of the inhibitory property of the ETB receptor on the epithelial sodium channel activity. 相似文献
18.
An investigation into the relationship between salivary cortisol,stress, anxiety and depression 总被引:3,自引:0,他引:3
Vedhara K Miles J Bennett P Plummer S Tallon D Brooks E Gale L Munnoch K Schreiber-Kounine C Fowler C Lightman S Sammon A Rayter Z Farndon J 《Biological psychology》2003,62(2):89-96
This study examined the relationship between indices of self-reported emotional distress and absolute versus change in cortisol levels. Fifty-four women attending a diagnostic breast clinic completed scales measuring stress, anxiety and depression and provided five saliva samples over the course of a single day for the measurement of cortisol. No significant relationships were evident between absolute cortisol levels and the distress measures. Analysis of the change in cortisol levels revealed a non-linear interaction effect between stress and anxiety and time of day. There was a non-linear relation between time of day and cortisol levels, but the extent of the non-linearity was dependent upon levels of stress and anxiety, not depression. A relationship was apparent between indices of distress and change in cortisol levels, but not absolute levels of the hormone. 相似文献
19.
Yin Xu Robert W McKenna Jeffrey E Doolittle Christa L Hladik Steven H Kroft 《Applied immunohistochemistry & molecular morphology》2005,13(2):116-123
The clinical and biologic relevance of the t(14;18) and features of germinal center (GC) differentiation in diffuse large B-cell lymphoma (DLBCL) remain controversial. The authors examined the association of t(14;18) with GC-associated markers and clinical features in 44 de novo DLBCLs (22 nodal and 22 primary extranodal). CD10, bcl-2, and bcl-6 were expressed in 50%, 62%, and 54% of cases respectively. There were no significant differences in expression of these markers between nodal and extranodal cases. Coexpression of CD10 and bcl-6 was seen in 12 of 41 cases, and was more frequent in nodal than extranodal DLBCL (9 of 21 vs. 3 of 20; P = 0.05). A CD10+/bcl-6+ phenotype was not significantly associated with bcl-2 expression, stage, complete remission rate, or survival. The t(14;18) was found in 7 of 44 (16%) cases (6 nodal, 1 extranodal; P = 0.09). It was associated with a CD10+/bcl-6+ phenotype (5 of 7 vs. 7 of 27; P = 0.015) and a trend toward more frequent bcl-6 expression (6 of 7 vs. 15 of 34; P = 0.09), but no association with bcl-2 expression, CD10, clinical stage, complete remission, or survival. Among nodal or high-stage (III-IV) DLBCL, cases with the t(14;18) showed a trend toward decreased survival (P = 0.12). 相似文献
20.
Mol A van Lieshout MI Dam-de Veen CG Neuenschwander S Hoerstrup SP Baaijens FP Bouten CV 《Biomaterials》2005,26(16):3113-3121
In cardiovascular tissue engineering approaches, efficient seeding methods are essential. To achieve this and to save time, cells can be encapsulated in gels. Combining the advantages of a gel as a cell carrier with the advantages of a fiber-based scaffold, providing structural integrity to the developing tissue, might offer several advantages. In this study, seeding by using fibrin as a cell carrier is compared to the conventional static seeding method with regard to tissue development. Seeding with fibrin resulted in less loss of soluble collagen into the medium and a more mature extracellular matrix in a shorter period of time. The use of fibrin degradation inhibitors was shown to inhibit extracellular matrix formation, although it did not hamper cell proliferation. The use of fibrin as a cell carrier to seed cells into a fiber-based scaffold may represent a promising, timesaving approach in cardiovascular tissue engineering applications. 相似文献