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We previously showed cell–cell contacts of human dermal fibroblasts to induce expression of the hepatocyte growth factor/scatter factor (HGF) in a process designated as nemosis. Now we report on nemosis initiation in bone marrow mesenchymal stem cells (BMSCs). Because BMSCs are being used increasingly in cell transplantation therapy we aimed to demonstrate a functional effect and benefit of BMSC nemosis for wound healing. Nemotic and monolayer cells were used to stimulate HaCaT keratinocyte migration in a scratch-wound healing assay. Both indicators of nemosis, HGF production and cyclooxygenase-2 expression, were induced in BMSC spheroids. When compared with a similar amount of cells as monolayer, nemotic cells induced keratinocyte in vitro scratch-wound healing in a concentration-dependent manner. The HGF receptor, c-Met, was rapidly phosphorylated in the nemosis-stimulated keratinocytes. Nemosis-induced in vitro scratch-wound healing was inhibited by an HGF-neutralizing antibody as well as the small molecule c-Met inhibitor, SU11274. HGF-induced in vitro scratch-wound healing was inhibited by PI3K inhibitors, wortmannin and LY294002, while LY303511, an inactive structural analogue of LY294002, had no effect. Inhibitors of the mitogen-activated protein kinases MEK/ERK1/2 (PD98059 and U0126), and p38 (SB203580) attenuated HGF-induced keratinocyte in vitro scratch-wound healing. We conclude that nemosis of BMSCs can induce keratinocyte in vitro scratch-wound healing, and that in this effect signaling via HGF/c-Met is involved.  相似文献   
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BACKGROUND: Maternal alloantibodies against the five common human platelet antigen (HPA) systems (HPA-1 to -3, -5, and -15) are found in only 20% of cases referred for fetal and neonatal thrombocytopenia (FMAIT) investigations. The question asked was whether mismatches for the remaining 11 low-frequency HPAs (HPA-4 and -6bw to -17bw) might in part explain the remaining 80% of cases.
STUDY DESIGN AND METHODS: A total of 1054 paternal DNA samples from referred FMAIT cases (among which 223 cases where antibodies against a common HPA were found) were genotyped for 11 low-frequency HPAs as well as a recently discovered polymorphism ( ITGA2B -C2320T). The initial genotyping was carried out by TaqMan and potential heterozygotes were confirmed by DNA sequencing. Clinical and serologic data were collected for each case with a heterozygote father.
RESULTS: In total, eight heterozygous fathers were identified: four for HPA-6w, one each for HPA-10w and -11w, and two for HPA-12w. Maternal antibodies against the corresponding antigen were identified in four of the eight cases. In two of these cases, antibodies against HPA-1a and HPA-1b were also found.
CONCLUSION: It was concluded that the minor alleles of HPA-4 and -6bw to -17bw are exceptionally rare in the Caucasian population and therefore do not explain the large number of FMAIT referrals which test negative for the common HPA antibodies.  相似文献   
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It is reported about a first successful program of gamete intra fallopian transfer (GIFT) as a supplement to intrauterine insemination and to in vitro fertilization (IVF). In 29 patients after HMG stimulation of the ovaries and laparoscopic aspiration of follicles recovered oocytes have been introduced together with prepared sperm via a special catheter directly into the ampulla of the oviduct. In 21 patients with different causes of infertility optimal stimulation conditions could be achieved. A pregnancy rate of 41.4% is the result of 29 GIFT events and 3 of them resulted in spontaneous term deliveries (10.3%).  相似文献   
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Previous studies have shown that recurrent severe hypoglycaemia can cause long-term cognitive impairment in children with type-1 diabetes, but the results are controversial, possibly due to the heterogeneity of samples and lack of comprehensive neuropsychological assessments of children. The aim of this study was to assess the effects of diabetes and severe hypoglycaemia on the neurocognitive functioning of children with a standardized, wide age-range neuropsychological test battery designed for the assessment of children. Eleven children with diabetes and a history of severe hypoglycaemia, 10 children with diabetes without a history of severe hypoglycaemia, and 10 healthy control children (a total of 31 children: 14 males and 17 females, age range 5 years 6 months to 11 years 11 months, mean 9 years 4 months, SD 1 year 11 months) were studied using the Wechsler Intelligence Scale for Children-Revised (WISC-R) and the NEPSY, a Developmental Neuropsychological Assessment. The NEPSY assessed development in attention and executive functions, language, sensorimotor functions, visuospatial processing, and learning and memory. Children with a history of severe hypoglycaemia had more neuropsychological impairments, more learning difficulties (as reported by parents), and needed more part-time special education than those in the other groups. Significant differences were found in verbal short-term memory and phonological processing. Results suggest that severe hypoglycaemia is a risk factor for learning due to deficits in auditory-verbal functioning.  相似文献   
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