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  • 1
    ISSN: 1524-475X
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: We have previously shown that fibroblasts obtained from adhesions produce greater amounts of transforming growth factor-beta 1 (TGF-β1) and extracellular matrix (ECM) molecules than normal fibroblasts isolated from normal peritoneum. The purpose of the current studies was to examine the effect of Tisseel (Baxter Healthcare Corporation, Glendale, CA), a fibrin sealant containing fibrinogen, aprotinin (a protease inhibitor), thrombin, and CaC12, on TGF-β1 and ECM production by human peritoneal mesothelial cells, normal peritoneal fibroblasts, and adhesion fibroblasts. Multiplex reverse transcription–polymerase chain reaction using β-actin as a housekeeping gene was used to determine mRNA levels of TGF-β1 and ECM in these cells at 6, 12, 24, and 48 hours under normoxic conditions in the following treatment groups :  fibrin sealant (Tisseel) alone; fibrin sealant with the two components diluted 1 : 2; fibrin sealant with the sealer protein component reconstituted without aprotinin (a protease inhibitor); fibrin sealant with the sealer protein component reconstituted without aprotinin (and both components diluted 1 : 2); fibrin sealant components diluted to physiologic concentrations; and control (culture media). The test compositions had little effect on TGF-β1 mRNA expression in mesothelial cells and normal peritoneal fibroblasts, but resulted in a marked reduction of TGF-β1 from adhesion fibroblasts. Expression of type I collagen by human peritoneal mesothelial cells was not detected; the compositions reduced type I collagen mRNA expression by both types of fibroblasts. Type III collagen was detected at six hours, and increased approximately 50 percent by culturing for 48 hours. Tisseel at full strength and with both components diluted 1 : 2 initially increased type III collagen mRNA levels; in contrast, type III collagen mRNA levels were reduced in mesothelial cells by the fibrin sealant without aprotinin at both concentrations and at physiologic concentrations. In both types of fibroblasts, the Tisseel compositions reduced type III collagen mRNA expression. Fibronectin mRNA were transiently reduced at six hours by approximately 50 percent in the presence of the Tisseel components, but then returned to control levels. Fibronectin mRNA levels were not altered in normal peritoneal fibroblasts, but were reduced by all but the physiologic concentration in adhesion fibroblasts. Tisseel may modulate human peritoneal mesothelial cell, normal peritoneal fibroblast, and adhesion fibroblast function. These results suggest that fibrin sealant prepared from the Tisseel kit without aprotinin has the ability to reduce ECM and TGF-β1 mRNA levels, especially from adhesion fibroblasts, which may indicate a role in reduction of postoperative adhesion development.
    Materialart: Digitale Medien
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  • 2
    ISSN: 1524-475X
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Overexpression and accumulation of extracellular matrix is central to peritoneal adhesion formation following surgically induced tissue trauma. Transforming growth factor-β1 and hypoxia have been implicated in tissue fibrosis and postoperative adhesion formation. To extend this observation we examined whether transforming growth factor-β1 and/or hypoxia regulate the expression of type I and III collagen in human peritoneal mesothelial cells. Cultured human mesothelial cells were maintained under hypoxia (2% oxygen), or treated with transforming growth factor-β1 (1 ng/ml) or a combination of hypoxia and transforming growth factor-β1. Total cellular RNA from treated and untreated cells were collected and subjected to multiplex reverse transcription/polymerase chain reaction to quantitate collagen I and III mRNA levels in response to these treatments. The results indicate that 6 hours of hypoxia increased collagen III mRNA by 7.2 fold which was further increased to 9.4 fold following transforming growth factor-β1 treatment; in contrast collagen I mRNA decreased by 0.42 fold which was further decreased by 0.3 fold following transforming growth factor-β1 treatment. Transforming growth factor-β1 treatment under normal conditions resulted in an 8.4-fold increase and a 0.3-fold decrease in collagen III and I mRNA levels, respectively. Hypoxia treatment also resulted in a 1.9-fold increase in transforming growth factor-β1 mRNA level compared with control. The ratio of type III/I collagen was increased in response to transforming growth factor-β1 treatment under hypoxic condition. In conclusion, the data suggest that hypoxia may modulate extracellular matrix production by human mesothelial cells via a transforming growth factor-β1 dependent mechanism.
    Materialart: Digitale Medien
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  • 3
    ISSN: 1471-0528
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Objective To comparatively analyse the expression of matrix metalloproteinase (MMP-3) and tissue inhibitor of MMP (TIMP-2) in serosal tissue of intraperitoneal organs and adhesions, as well as peritoneal fluid and serum of subjects with and without adhesions.Design Cross sectional study.Setting Academic research centres.Sample Patients undergoing abdominal/pelvic surgery.Methods Messenger ribonucleic acid (mRNA) and protein expression using quantitative reverse transcription polymerase chain reaction (Q-RT-PCR), ELISA and immunohistochemistry.Results All the tissues examined express MMP-3 and TIMP-2 mRNA and protein at consistently varying levels ranging from 100- to 1000-fold and 2- to 10-fold mRNA and protein, respectively. Serosa of uterine, fallopian tube, ovary and partial peritoneum express a higher MMP-3 mRNA compared with small and large bowels and omentum, while TIMP-2 expression was less variable with the highest level found in uterine serosa (P 〈 0.05). The expression of MMP-3 and TIMP-2 mRNA in adhesions was not significantly different compared with parietal peritoneum. MMP-3 and TIMP-2 protein content in tissue extracts, peritoneal fluids and serum also varied with higher TIMP-2 than MMP-3 (P 〈 0.05). TIMP-2 levels were lower in serum of subjects with moderate/extensive adhesions compared with subjects without adhesions. Immunoreactive MMP-3 and TIMP-2 proteins were detected in various cell types in these tissues. There was no correlation between MMP-3 and TIMP-2 expression, and age, gender or menstrual status of subjects with or without adhesions.Conclusion MMP-3 and TIMP-2 are expressed at varying levels in serosal tissues of peritoneal organs and adhesions, with higher TIMP-2 than MMP-3. Based on the knowledge that tissue injury alters the expression of MMPs and TIMPs, such variations may predispose an organ to develop more adhesions than others. In addition, the results suggest that serum level of TIMP-2 may represent a marker for subjects who will form adhesions with greater severity.
    Materialart: Digitale Medien
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  • 4
    Digitale Medien
    Digitale Medien
    [s.l.] : Nature Publishing Group
    Nature 429 (2004), S. 154-154 
    ISSN: 1476-4687
    Quelle: Nature Archives 1869 - 2009
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Notizen: [Auszug] Even though the genetic fingerprint of human sperm has been defined, its role in orchestrating fertilization and the development of the early embryo remains vague. Here we show that human male gametes pass over more to the oocyte than just the haploid male genome — paternal messenger RNAs ...
    Materialart: Digitale Medien
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  • 5
    ISSN: 1573-7330
    Schlagwort(e): in vitro fertilization-embryo transfer ; ovarian hyperstimulation ; clomiphene citrate ; human menopausal gonadotropins
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Various protocols have been utilized for stimulation of multiple ovarian follicles in patients undergoing in vitro fertilization-embryo transfer (IVF-ET). Previous studies have suggested that the combination of clomiphene citrate (CC) and human menopausal gonadotropins (hMG) is superior to either CC or hMG alone in terms of follicular development, oocyte recovery, and embryo transfer. However, no significant increase in viable pregnancy rates has been reported with any of the protocols. This report examines five different CC/hMG protocols. While differences were seen in terms of serum estradiol response and fertilization rates of mature oocytes among the various protocols, no significant differences were found in terms of follicular development, oocyte recovery, embryo transfer, or pregnancy. The pregnancy rate in IVF-ET appears unaffected by variations in the dose and timing of CC and hMG in a combination protocol.
    Materialart: Digitale Medien
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    Journal of assisted reproduction and genetics 5 (1988), S. 167-170 
    ISSN: 1573-7330
    Schlagwort(e): embryo cleavage ; incubation temperature
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract We have studied the effect of an elevated incubation temperature on the in vitro cleavage rate of one- and two-cell mouse embryos. Two-cell embryos demonstrated a significantly higher rate of cleavage when incubated at 39°C as compared to 37 or 41°C. When recovered at the onecell stage, the difference in cleavage rate between the groups incubated at 37 and 39°C did not reach significance. While the morphology of the embryos incubated at 37°C did not differ from that of the embryos incubated at 39°C in either group, a significantly higher rate of degeneration was noted in the group of two-cell embryos incubated at 41°C. These findings may apply to the human in vitro fertilization and embryo transfer system (IVF-ET), where the existing “lag” between embryo and endometrium could be narrowed if embryo cleavage rates could be accelerated. Further documentation of the normality of these “advanced” embryos is required.
    Materialart: Digitale Medien
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Journal of assisted reproduction and genetics 4 (1987), S. 205-217 
    ISSN: 1573-7330
    Schlagwort(e): follicular and oocyte maturation ; intrafollicular markers ; in vitro fertilization
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The use of ovulation induction for multiple follicular growth in in vitro fertilization (IVF) has introduced the problem of follicular asynchrony. As a consequence of the asynchrony, the parameters most commonly used by IVF groups to assess follicular and oocyte quality within those follicles are not sufficiently sensitive or specific. Thus, each follicle must be considered separately, and specific markers of follicular and/or oocyte maturation must be sought from within the follicle. In this review we analyze previous reports of potential markers of follicular and oocyte maturation. In regards to the follicular fluid constituents, the level of estradiol in follicular fluid correlates with fertilization and pregnancy in stimulated cycles. Other steroids are only helpful when specific stimulation protocols are used. The level of some follicular proteins such as alpha-1-antitrypsin and fibrinogen also correlates with fertilization and pregnancy outcome. Cyclic AMP levels in follicular fluid are significantly reduced in follicles leading to conception. Regulators of oocyte maturation, such as the Oocyte Maturation Inhibitor (OMI) or the Meiosis Inducing Substance (MIS) have also been correlated with IVF outcome, but their exact structure remains still unknown. In addition, other sophisticated parameters, such as chemotactic activity of human leukocytes, or simple methods, such as the presence of intrafollicular echoes, have also been used as successful markers in predicting IVF outcome.
    Materialart: Digitale Medien
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  • 8
    Digitale Medien
    Digitale Medien
    Springer
    Journal of assisted reproduction and genetics 4 (1987), S. 251-255 
    ISSN: 1573-7330
    Schlagwort(e): ovulation induction ; consecutive menstrual cycles ; estradiol
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract It has been theorized that the administration of human menopausal gonadotropin (hMG) in consecutive menstrual cycles will result in a poor follicular response in the second cycle. To examine this, 50 women undergoing ovulation induction in two consecutive cycles were assessed, using in each the same induction regimen during the initial 5 days. The remainder of each cycle was individualized according to their response. Nine women were anovulatory, 19 were oligoovulatory, and 22 ovulated regularly in unstimulated cycles. In repeat cycles only 3 of 50 had poor follicular development and did not receive human chorionic gonadotropin (hCG); all were anovulatory. Forty-two of 50 of the first cycles had continually rising estradiol (E2), while 43 of 47 of the second cycles had rising E2 patterns. Grouping the peak E2 prior to hCG in the ranges 〈300, 300–699, 700–1099, and ⩾1100 pg/ml, peaks in the second cycle were similar in 25 of 50, lower in 16, and higher in 9. Only 3 of 9 anovulatory women had similar peaks, as compared to 22 of 41 of the oligoovulatory and regularly ovulating women. Comparing the second to the first cycle, the day of hCG was within 1 day in 28 of 50 women, 2 or more days less than the first cycle in 6, and 2 or more days greater than the first cycle in 11. We conclude that in a successive cycle of ovulation induction (i) the follicular response is impaired in anovulatory women, but (ii) in oligoovulatory or regularly ovulating women, clinically significant differences in the estradiol response do not occur.
    Materialart: Digitale Medien
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  • 9
    ISSN: 1573-7330
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Patients' response to daily ultrasound scanning by either a transvaginal or a transabdominal method for the purpose of monitoring the ovarian response to gonadotropin therapy in an in vitro fertilization and embryo transfer program has been evaluated. A questionnaire was used to determine various aspects of these two procedures, sources of discontent, and the patients' preference. The vast majority of patients reported less discomfort and generally preferred the transvaginal over the transabdominal scanning method. The transvaginal method is easy to perform, affords excellent visualization of the pelvic organs, and in addition, is clearly preferred by patients over the transabdominal technique. We recommend its use in patients monitored for IVF-ET and for a variety of other clinical conditions requiring detailed evaluation of the pelvic organs.
    Materialart: Digitale Medien
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  • 10
    Digitale Medien
    Digitale Medien
    Springer
    Journal of assisted reproduction and genetics 3 (1986), S. 106-109 
    ISSN: 1573-7330
    Schlagwort(e): in vitro fertilization ; clomiphene citrate ; antiestrogenic effect ; cervical mucus
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract End-organ antiestrogenic effects of clomiphene citrate (CC) have been demonstrated in the female reproductive tract at the levels of the ovary, cervix, and endometrium. However, it has not been established whether this effect is manifested during concomitant human menopausal gonadotropin (hMG) administration, as occurs in hMG/ CC stimulations of multiple follicular development. To assess this question a review was made of serum estradiol (E2) and cervical mucus in 47 hMG and 56 hMG/CC stimulations on days-2,-1,0, and+1 relative to the day of hCG administration. E2 levels (pg/ml) were significantly lower in the hMG as compared to the hMG/CC group. However, comparing the hMG and hMG/CC groups, cervical mucus scores were significantly higher in the former. Furthermore, an analysis of covariance demonstrated that the cervical mucus scores on each day were significantly lower in the hMG/CC group (P〈0.001). Thus, in hMG/CC stimulations for in vitro fertilization (IVF), despite the concomitant administration of pharmacologic doses of hMG, CC exerts an antiestrogenic effect on at least one end organ, cervical mucus production. Potentially, this antiestrogenic effect in IVF stimulations would be exerted at other female reproductive tract sites including the endometrium; however, its clinical significance, if any, is unclear.
    Materialart: Digitale Medien
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