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The role of growth factors and cytokines in the impaired healing of chronic leg ulcers remains uncertain. The aim of this study was to determine whether changes in the amount and location of cytokines and growth factors may be associated with impaired healing in chronic leg ulcers. Biopsies from leg ulcers of 21 patients and from normal skin of nine healthy volunteers were examined immunohistochemically for selected growth factors and cytokines. Greater staining intensity was found in keratinocytes at the edges of ulcers compared to normal skin, or skin adjacent to the ulcers. Staining at the ulcer edge was more intense in nonhealing ulcers for only vascular endothelial growth factor and platelet-derived growth factor, whereas staining in the adjacent skin was more intense for all factors in the nonhealing phase. For all factors staining was cytoplasmic, suggesting production in these areas. This study shows up-regulation of the production of cytokines and growth factors in keratinocytes of chronic leg ulcers that is greater when the ulcers are nonhealing. 相似文献
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Picotamide inhibition of excess in vitro thromboxane B2 release by colorectal mucosa in inflammatory bowel disease. 总被引:1,自引:0,他引:1
Collins CE Benson MJ Burnham WR Rampton DS 《Alimentary pharmacology & therapeutics》1996,10(3):315-320
BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease. 相似文献
8.
Anderson RA; Evans LW; Irvine DS; McIntyre MA; Groome NP; Riley SC 《Human reproduction (Oxford, England)》1998,13(12):3319-3325
Follistatin is a binding protein for the activin and inhibin family of
hormones, regulating their biological activity. In the male reproductive
tract, the interaction of these factors is likely to be involved in the
regulation of the proliferation of several cell types. We have investigated
the presence of follistatin and activin A in seminal plasma using specific
immunoassays and have localized follistatin and activin/inhibin subunits in
the adult human testis, prostate and seminal vesicle to establish their
likely sources. High concentrations of immunoreactive follistatin were
present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in
peripheral plasma) and were similar in men with oligo/azoospermia and
following vasectomy. Follistatin immunoreactivity was localized to both
Leydig and Sertoli cells of the testis, and to epithelial cells of the
prostate gland and seminal vesicle, which are likely to be the predominant
sources of the hormone in seminal plasma. Activin A was also present in
seminal plasma in normal men but was undetectable following vasectomy, thus
deriving from the testis. Consistent with this finding, the betaA-subunit
was immunolocalized in Sertoli and Leydig cells but was not present in
seminal vesicle or prostate gland. The functional significance of the high
concentrations of follistatin secreted into seminal plasma by the prostate
gland and/or seminal vesicle is uncertain, but they may regulate the
biological activity of testis-derived activin A and inhibin B.
相似文献
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Dohle GR; Ramos L; Pieters MH; Braat DD; Weber RF 《Human reproduction (Oxford, England)》1998,13(3):620-623
Male genital tract obstructions may result from infections, previous
inguinal and scrotal surgery (vasectomy) and congenital bilateral absence
of the vas deferens (CBAVD). Microsurgery can sometimes be successful in
treating the obstruction. In other cases and in cases of failed surgical
intervention, the patient can be treated by microsurgical or percutaneous
epididymal sperm aspiration (MESA, PESA) or testicular sperm extraction
(TESE) and intracytoplasmic sperm injection (ICSI). We present the results
of 39 ICSI procedures for obstructive azoospermia in 24 couples. The
aetiology of the obstruction was failed microsurgery in 11 patients, CBAVD
in nine and genital infections in four. Sperm retrieval was accomplished
via MESA in four cases, PESA in 18 cases and via TESE in 11 cases. TESE was
only applied when PESA failed to produce enough spermatozoa for
simultaneous ICSI. In six patients, the ICSI procedure was performed with
cryopreserved spermatozoa after an initial PESA procedure. Fertilization
occurred in 47% of the metaphase II oocytes; embryo transfer was performed
in 92% of procedures and resulted in a clinical pregnancy in 13/39
procedures. Ongoing pregnancy was achieved in 10/39 procedures. One
pregnancy was terminated early after prenatal investigation showed a
cytogenetic abnormality (47,XX+18, Edwards syndrome). The other nine
pregnancies resulted in the live birth of 10 children, without any
congenital abnormalities. Epididymal and testicular retrieved spermatozoa
were successfully used for ICSI to treat obstructive azoospermia, and
resulted in an ongoing pregnancy in 10 of 24 couples (41.6%) after 39 ICSI
procedures, a success rate of 25.6% per treatment cycle and of 27.7% per
embryo transfer.
相似文献
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