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21.
Reliable immunohistochemical detection of collagen in formalin fixed, paraffin embedded tissues requires protease digestion. While these pan-proteases (pepsin, trypsin, protease K, etc.) enhance collagen detection, they also digest many other tissue proteins and produce poor cellular morphology and unrecognizable cellular structures. Balancing the conditions (protease type, concentration, incubation time and temperature) to digest some, but not all, proteins in a tissue section while optimizing collagen detection requires one to compromise improved collagen immunolabeling with adequate cellular morphology. Furthermore, optimal conditions for digesting tissue proteins to enhance collagen detection vary among tissue types and their fixation. Although brain is not typically subject to these deleterious consequences, structures such as epithelium, spermatids, stroma etc. and other tissues with complicated histology are profoundly affected. To resolve this technical dilemma, we discovered a novel use for collagenase to enhance collagen immunodetection without affecting the noncollagen proteins, thereby preserving tissue morphology. Collagenase, which is typically used in vitro for disassociation of cells, has never been used reliably on formalin fixed, paraffin embedded tissue sections. This new use of collagenase for immunohistochemistry promotes increased collagen immunolabeling, is easy to use, is versatile, and allows preservation of tissue structure that provides maximal and accurate histological information.  相似文献   
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Many viruses alter different stages of apoptosis of infected cells as a strategy for successful infection. Few studies have addressed mechanisms of equine herpesvirus 1 (EHV-1) strain-induced cell death. We investigated the effect of an abortigenic strain (AR8 strain) on heterologous Madin–Darby bovine kidney cells and homologous equine dermis (ED) cells cell lines. We compared morphologic and biochemical features of early and late apoptosis at different postinfection times. We investigated translocation of phosphatidylserine to the cell surface, nuclear fragmentation and changes in the cytoskeleton using flow cytometry and annexin V/propidium iodide staining, DNA laddering, terminal deoxynucleotidyl transferase UTP nick-end labeling assay and immunofluorescence staining of cytokeratin 18 cleavage. AR8 EVH-1 strain interfered with apoptosis in both cell lines, particularly during the middle stage of the replication cycle; this was more evident in ED cells. Although this antiapoptotic effect has been reported for other alpha herpesviruses, our findings may help elucidate how EHV-1 improves its infectivity during its cycle.  相似文献   
24.
Jailing of a side-branch is a known complication of stent implantation, and makes access to the side-branch difficult, especially if the stent is of the self-expanding type. Although plain balloon angioplasty is feasible for the jailed side-branches, the use of newer devices (a stent, Rotablation or atherectomy) has not been described. We describe a novel way of treating a side-branch jailed by a self-expanding stent by using stent implantation through the strut of a self-expanding stent.  相似文献   
25.
Summary Dotted (Dt) is the regulatory element of a two-unit controlling system in maize. Dt causes the inherited change from the recessive a (colorless) to its dominant allele, A (anthocyanin production), during the development of the stalk, leaves, and endosperm. The mutation events are observed as sectors of color in an anthocyaninless background.Since its discovery over 40 years ago, Dt has always been found in the terminal knob of the short arm of chromosome 9. This is puzzling because controlling and regulatory elements in general are not located permanently, but change positions (transpose) within the chromosomal complement. To resolve this seeming discrepancy, transpositions were looked for in a homozygous a Dt stock. Because the frequency of aleurone mutations is exponentially related to Dt dosage, a Dt transposition would result in a greatly increased number of dots if the egg or sperm nucleus contained both the transposed Dt and the Dt remaining on chromosome 9. A total of 6 transposed Dt's (Dt-T) were recovered in this manner. Dt-TA was found linked to the gene Y (yellow endosperm) of chromosome 6. Dt-TB no longer showed linkage with yg2 of chromosome 9, but remains unlocated (the original Dt in this stock is separated from yg2 by 6 or 7 cross-over units.). The remaining transpositions (C-F) assorted independently of Dt on chromosome 9.The transposed Dt's had the same effect as Dt on the frequency and timing of aleurone mutations. An increase in transposition frequency and losses of Dt-T's was characteristic of several of the transposed Dt's. Dt-T's B-F transposed so frequently that testcross ratios of 71 (three Dt' s) and 15 1 (four Dt' s) were observed. No secondary transpositions or losses of Dt-TA were detected. Thus, Dt-TA resembles the original Dt with regard to its transposition frequency and stability.Journal Paper No. J-8333 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 1880.  相似文献   
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27.

Introduction

Sclerostin levels have been reported to be low in ankylosing spondylitis (AS), but there is no data regarding the possible role of this Wnt inhibitor during anti-tumor necrosis factor (TNF) therapy. The present study longitudinally evaluated sclerostin levels, inflammatory markers and bone mineral density (BMD) in AS patients under anti-TNF therapy.

Methods

Thirty active AS patients were assessed at baseline, 6 and 12 months after anti-TNF therapy regarding clinical parameters, inflammatory markers, BMD and baseline radiographic damage (mSASSS). Thirty age- and sex-matched healthy individuals comprised the control group. Patients'' sclerostin levels, sclerostin binding low-density lipoprotein receptor-related protein 6 (LRP6) and BMD were evaluated at the same time points and compared to controls.

Results

At baseline, AS patients had lower sclerostin levels (60.5 ± 32.7 vs. 96.7 ± 52.9 pmol/L, P = 0.002) and comparable sclerostin binding to LRP6 (P = 0.387) than controls. Improvement of Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), Bath Ankylosing Spondylitis Metrology Index (BASMI), Ankylosing Spondylitis quality of life (ASQoL) was observed at baseline vs. 6 vs. 12 months (P < 0.01). Concomitantly, a gradual increase in spine BMD (P < 0.001) and a positive correlation between baseline mSASSS and spine BMD was found (r = 0.468, P < 0.01). Inflammatory parameters reduction was observed comparing baseline vs. 6 vs. 12 months (P <0.01). Sclerostin levels progressively increased [baseline (60.5 ± 32.7) vs. 6 months (67.1 ± 31.9) vs. 12 months (72.7 ± 32.3) pmol/L, P <0.001]. At 12 months, the sclerostin levels remained significantly lower in patients compared to controls (72.7 ± 32.3 vs. 96.70 ± 52.85 pmol/L, P = 0.038). Moreover, sclerostin serum levels at 12 months were lower in the 10 patients with high C reactive protein (CRP) (≥ 5 mg/l) compared to the other 20 patients with normal CRP (P = 0.004). Of note, these 10 patients with persistent inflammation also had lower sclerostin serum levels at baseline compared to the other patients (P = 0.023). Univariate logistic regression analysis demonstrated that AS patients with lower sclerostin serum levels had an increased risk to have high CRP at 12 months (odds ratio = 7.43, 95% CI 1.23 to 45.01, P = 0.020) than those with higher sclerostin values.

Conclusions

Persistent low sclerostin levels may underlie continuous inflammation in AS patients under anti-TNF therapy.  相似文献   
28.

Background  

Many commercial banana varieties lack sources of resistance to pests and diseases, as a consequence of sterility and narrow genetic background. Fertile wild relatives, by contrast, possess greater variability and represent potential sources of disease resistance genes (R-genes). The largest known family of plant R-genes encode proteins with nucleotide-binding site (NBS) and C-terminal leucine-rich repeat (LRR) domains. Conserved motifs in such genes in diverse plant species offer a means for isolation of candidate genes in banana which may be involved in plant defence.  相似文献   
29.
The present study was conducted to identify polymorphisms in CACNA2D1 gene and their association with clinical mastitis and production traits. Exon 18 and its flanking regions were screened for the presence of SNPs. Statistical analysis was performed to identify association of period of birth, breed, and genotype with mastitis incidence on randomly selected 103 Sahiwal and 102 Karan Fries cattle. PCR-RFLP analysis revealed that g.38819398G?>?A mutation in exon 18 (269?bp amplicon) of CACNA2D1 gene resolved into AA, AG, and GG genotypes in Sahiwal and Karan Fries cattle. Wald chi-square analysis revealed that the period of birth, breed, and genotype were significantly associated with mastitis incidence. GG genotyped cattle were found to be less susceptible to mastitis. Least square analysis revealed that GG and AG genotype animals of G38819398A SNP of CACNA2D1 gene in Sahiwal as well as in Karan Fries cattle were associated with higher average milk yields during 1st, 2nd, and 3rd lactations (P?<?0.01). These observations and their differential association with the incidence of mastitis and production traits can be utilized as an aid to selection for simultaneous improvement of both antagonistic traits; however, validation of results on large number of animals is warranted.  相似文献   
30.
Using a murine model of sepsis, we found that the balance of tissue pro- to anti-inflammatory cytokines directly correlated with severity of infection and mortality. Sepsis was induced in C57BL/6 mice by cecal ligation and puncture (CLP). Liver tissue was analyzed for levels of IL-1beta, IL-1 receptor antagonist (IL-1ra), tumor necrosis factor (TNF)-alpha, and soluble TNF receptor 1 by ELISA. Bacterial DNA was measured using quantitative real-time PCR. After CLP, early predominance of proinflammatory cytokines (6 h) transitioned to anti-inflammatory predominance at 24 h. The elevated anti-inflammatory cytokines were mirrored by increased tissue bacterial levels. The degree of anti-inflammatory response compared with proinflammatory response correlated with the bacterial concentration. To modulate the timing of the anti-inflammatory response, mice were treated with IL-1ra before CLP. This resulted in decreased proinflammatory cytokines, earlier bacterial load, and increased mortality. These studies show that the initial tissue proinflammatory response to sepsis is followed by an anti-inflammatory response. The anti-inflammatory phase is associated with increased bacterial load and mortality. These data suggest that it is the timing and magnitude of the anti-inflammatory response that predicts severity of infection in a murine model of sepsis.  相似文献   
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