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41.
Ghosh R  Gu G  Tillman E  Yuan J  Wang Y  Fazli L  Rennie PS  Kasper S 《The Prostate》2007,67(10):1038-1052
BACKGROUND: Proteins which regulate normal development may promote tumorigenesis, tumor progression, or metastasis through dysregulation of these functions. We postulate that proteins, which regulate prostate growth also promote prostate cancer (PCa) progression. METHODS: Two Dimensional Gel Electrophoresis was utilized to compare patterns of protein expression in 12T-7f prostates (LPB-Tag mouse model for PCa) during tumor development and progression with those of normal developing and adult wild type CD-1 prostates. Stathmin expression and phosphorylation patterns were analyzed in mouse and human PCa cell lines as well as in human PCa tissue arrays. RESULTS: Stathmin was identified by two-dimensional gel electrophoresis and mass spectrometry. Stathmin levels increase early during normal mouse prostate development and again during prostate tumor development and progression. In human prostate adenocarcinoma, stathmin increases in Gleason pattern 5. Further, stathmin is differentially phosphorylated in androgen-dependent LNCaP cells compared to androgen-independent PC-3 and DU145 cells. This differential phosphorylation is modulated by androgen and anti-androgen treatment. CONCLUSION: Stathmin expression is highest when the prostate is undergoing morphogenesis or tumorigenesis and these processes may be regulated through differential phosphorylation. Furthermore, modulation of stathmin phosphorylation may correlate with the development of androgen-independent PCa.  相似文献   
42.
Complement is a multifunctional system of receptors and regulators as well as effector molecules. Both the pathogenic and diagnostic power of complement is based on the capacity of the complement system to amplify innate and adaptive immunity. This amplification is accomplished through two strategies: (1) enzymatic reactions in the complement cascade, and (2) stimulation of leukocytes, platelets and parenchymal cells through specific receptors or receptor-independent pore formation. The mechanisms by which complement mediates and modifies nonspecific inflammation, antibody-mediated injury and T-cell responses are of particular significance to the pathogenesis of transplant rejection. Understanding the mechanisms by which complement integrates the interactions of leukocytes, platelets and parenchymal cells offers opportunities to further refine the diagnosis of rejection.  相似文献   
43.
Introduction : Hypertrophic scar is a devastating sequel to burns and other tangential skin injuries. It follows deep dermal injuries and does not occur after superficial injuries. Nitric oxide (NO) plays many important roles in wound healing from inflammation to scar remodeling. Studies have shown that expression of nitric oxide synthase and nitric oxide production are decreased in human hypertrophic scar. However little is known about NO involvement in the early stages of hypertrophic scarring, because of the lack of an animal model. It was recently reported that the female red Duroc pig (FRDP) makes thick scar, which is similar to human hypertrophic scar. We hypothesized that NO production in wounds on the female, red Duroc pig is similar to that of human hypertrophic scar and that NO involvement in deep wounds is different from that in superficial wounds. Methods : Superficial (0.015” to 0.030”) and deep (0.045” to 0.060”) wounds were created on the backs of four FRDPs. Biopsies were collected at weeks 1.5, 4, 8 and 21 post wounding including samples of uninjured skin. Nitric oxide levels were measured with the Griess reaction assay and normalized with tissue protein level. Results : Superficial wounds healed with an invisible scar whereas the deep wounds healed with scar resembling mild hypertrophic scar. The thickness of the scars from the deep wounds was significantly greater than uninjured skin and healed superficial wounds (p < 0.01). NO levels were increased at 1.5 weeks in deep wounds compared to superficial wounds and uninjured skin (p < 0.05). At 8 weeks, NO levels in deep wounds had returned to the level of uninjured tissue and superficial wounds. By 21 weeks, NO levels had decreased significantly when compared to superficial wounds (p < 0.01). There were no differences in NO levels between uninjured skin and superficial wounds at any time point (p > 0.05). Conclusions : NO production is similar in late, deep wounds on the female, red Duroc pig to that reported in the literature for human hypertrophic scar further validating this animal model. NO production is quite different after deep wounds as compared to superficial wounds in the FRDP. Early elevation in nitric oxide production might account for excessive inflammation in deep wounds that become thick scars in the FRDP. Nitric oxide regulators and effects at early stages of scar formation should be elucidated further and the FRDP appears to be a useful model.  相似文献   
44.
Epitopes for 22 alloantibodies that inhibit factor VIII procoagulant protein (FVIII) from multitransfused individuals with severe hemophilia A and three autoantibodies from nonhemophilic individuals appeared to be restricted to two specific regions of the FVIII molecule. Immunoblotting of purified FVIII and purified thrombin-degraded FVIII, followed by reaction with inhibitor plasma samples, monoclonal anti-human IgG3 and IgG4 antibodies, and radiolabeled affinity-purified rabbit anti-mouse IgG, revealed that inhibitor epitopes could be localized to the Mr 72,000 and Mr 44,000 thrombin fragments of FVIII. These two chains are located at the carboxyl terminus and near the amino terminus of the FVIII molecule, respectively. The pattern of reactivity of the inhibitor alloantibodies could be divided into three types: 10 reacted with the Mr 72,000 chain, 3 reacted with the Mr 44,000 chain, and 9 reacted with both of these chains. Among the 3 inhibitor autoantibodies, 1 of each type was found. Ten normal plasmas, as well as 14 plasmas from multitransfused individuals with severe hemophilia A and no inhibitor, were not reactive with the FVIII immunoblots. However, one multitransfused individual with severe hemophilia A and no detectable inhibitor revealed the presence of an antibody reactive with the middle section of the FVIII molecule. The existence of FVIII inhibitor epitopes on both the Mr 72,000 and Mr 44,000 chains raises the possibility that these epitopes might be further restricted to regions of homology between the two chains. These data suggest the possibility of designing inhibitor blocking polypeptides for use as therapeutic agents.  相似文献   
45.
To evaluate the risk of heterosexual transmission of the acquired immunodeficiency syndrome, lymphadenopathy, and infection with human T-lymphotropic virus type III (HTLV-III), we studied 42 hemophiliacs and their wives. By early 1984, 9 of the hemophiliacs had asymptomatic lymphadenopathy and 1 had the acquired immunodeficiency syndrome. Twenty-one hemophiliacs, including all 10 with clinically overt disease, had antibody to HTLV-III. None of the 42 wives had lymphadenopathy or the acquired immunodeficiency syndrome but 2 had HTLV-III antibody. One of these women had evidence of immunologic dysfunction with a markedly reduced T-helper/suppressor cell ratio. The husbands of these 2 women both had HTLV-III antibody, but neither had overt acquired immunodeficiency syndrome-related disease. Thus, as of early 1984, the prevalence of HTLV-III antibody in wives of hemophiliacs seropositive for HTLV-III was 9.5% (2 of 21). We conclude that transmission of HTLV-III occurs between hemophiliacs and their heterosexual partners.  相似文献   
46.
The coding nucleotide sequence of the mRNA for NADPH-cytochrome P-450 oxidoreductase (NADPH:ferricytochrome oxidoreductase, EC 1.6.2.4) from rat liver was determined from two overlapping cDNA clones, pOR-7 and pOR-8, which together contain 2401 nucleotides complementary to rat liver oxidoreductase mRNA. The single open reading frame of 2034 nucleotides spanning these cDNAs codes for a 678 amino acid polypeptide with a molecular weight of 76,962. The deduced amino acid composition is in excellent agreement with that determined by direct amino acid analysis of purified rat liver P-450 oxidoreductase, and the amino-terminal region (residues 1-80) largely coincides with the amino-terminal sequence of the oxidoreductase isolated from rabbit liver. Comparison of the amino acid sequence to those of other flavoproteins revealed two separate domains that are likely to be involved in flavin binding: a long segment (residues 77-228) homologous with Desulfovibrio vulgaris flavodoxin, an FMN-containing protein, and a shorter segment (residues 452-477) homologous with the FAD-binding segment of fumarate reductase from Escherichia coli.  相似文献   
47.
PURPOSE: To assess the analgesic efficacy and functional outcome of postoperative epidural infusion of ropivacaine combined with sufentanil in a randomized, controlled trial. METHODS: Thirty-two ASA I-III patients undergoing elective total hip replacement (THR) were included. Lumbar epidural block using 0.75% ropivacaine was combined with either propofol sedation or general anesthesia for surgery. On arrival in the recovery room, the epidural infusion was commenced at a rate in mL calculated as follows: (height in cm - 100) x 0.1. Eleven patients received an epidural infusion of ropivacaine 0.1% with 0.5 microg x mL(-1) sufentanil (Group R+S0.5), ten patients ropivacaine 0.1% with 0.75 microg x mL(-1) sufentanil (Group R+S0.75), and 11 patients ropivacaine 0.1% with 1 microg x mL(-1) sufentanil (Group R+S1) over a postoperative study period of 44 hr. All patients had access to iv piritramide via a patient-controlled analgesia (PCA) device. Postel-Merle-d'Aubigné scoring system (PMA score) was assessed preoperatively, three weeks after surgery, and three months after surgery by an orthopedic surgeon blinded to study group. RESULTS: Motor block was negligible in all three groups. After eight hours of epidural infusion, sensory block had regressed completely in all patients. There was no significant difference with regard to visual analogue scale (VAS) scores (at rest: P = 0.55, on movement: P = 0.63), consumption of rescue medication (P = 0.99), patient satisfaction (P = 0.22), and the incidence of adverse events. All treatment regimens provided effective postoperative analgesia with only a minimal use of supplemental opioid PCA. There was no difference between groups regarding orthopedic PMA score (pain: P = 0.24, mobility: P = 0.65, and ability to walk: P = 0.44). CONCLUSION: Ropivacaine 0.1% with 0.5 microg x mL(-1) sufentanil for postoperative analgesia after THR provides efficient pain relief and, compared with 0.75 and 1 microg x mL(-1) sufentanil, reduces sufentanil consumption without compromise in patient satisfaction, VAS scores, and functional outcome.  相似文献   
48.
BACKGROUND: Recent advances in the understanding of immunomodulatory properties of phosphodiesterase 4 (PDE4) inhibitors recommend these drugs for immunosuppressive therapy after lung transplantation. The potency of three PDE4 inhibitors was tested using an established model of heterotopic tracheal transplantation in rats. METHODS: Five allogenic groups were investigated and treated with the PDE4 inhibitors: rolipram, cilomilast (Ariflo, SB-207499, SmithKline Beecham, Munich, Germany), roflumilast (Altana Pharmacia, Bad Homburg, Germany) or cyclosporine A (CsA), or left without immunosuppression. The grafts were quantitatively analyzed for epithelial integrity, monocyte/macrophage content, cell proliferation, and tracheal obliteration by histology/immunohistochemistry (days 1, 5, 7, 21, 28; n=4-7). RESULTS: In animals treated with the PDE4 inhibitors, the epithelium was completely lost until day 21. The epithelium was partially preserved in the rats receiving CsA until day 28. In the acute phase (days 5 and 7) the infiltration of monocytes and macrophages was significantly inhibited similarly (cilomilast) or less effective (rolipram, roflumilast) as in CsA-treated rats. In the chronic phase (day 28) the significant increase of monocytes and macrophages after CsA-treatment was not found in PDE4 inhibitor-treated rats. The PDE4 inhibitors showed lower (rolipram) or higher (cilomilast, roflumilast) potency as CsA to inhibit the cell proliferation. Only treatment with PDE4 inhibitor (Ariflo) significantly inhibited the obliteration, but to a lesser degree as CsA. CONCLUSION: The PDE4 inhibitors tested in our study are not suitable on their own for immunosuppressive therapy after lung transplantation because of the limited protection against the epithelial disturbance, infiltration of immune cells, and luminal obliteration. The strong anti-proliferative effect of the second-generation PDE4 inhibitors, cilomilast and roflumilast, suggest a benefit for the effective inhibition of immune cell and fibroblast proliferation contributing to the development of obliterative bronchiolitis.  相似文献   
49.
50.

Purpose  

Transplantation surgery suffers from a shortage of donor organs worldwide. Cell injection and tissue engineering (TE), thus emerge as alternative therapy options. The purpose of this article is to review the progress of TE technology, focusing on mesenchymal stem cells (MSC) as a cell source for artificial functional tissue.  相似文献   
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