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31.
Ccile Toly‐Ndour Stphanie Huguet‐Jacquot Agns Mailloux Hlne Delaby Giorgia Canellini Martin L. Olsson Agneta Wikman Joke M. Koelewijn Jean‐Marc Minon Tobias J. Legler Frederik B. Clausen Mark Lambert Helen Ryan Irena Bricl Sys Hasslund Agnieszka Orzinska Katarzyna Guz Malgorzata Uhrynowska Antonella Matteocci Nuria Nogues Eduardo Muniz‐Diaz Susanna Sainio Masja De Haas C. Ellen Van der Schoot 《ISBT科学丛刊》2021,16(1):106-118
32.
Devin L. Ward Lauren Schroeder Emma Pomeroy Jocelyn E. Roy Laura T. Buck Jay T. Stock Malgorzata Martin-Gronert Susan E. Ozanne Mary T. Silcox T. Bence Viola 《Anatomical record (Hoboken, N.J. : 2007)》2021,304(12):2645-2660
Maternal malnutrition during gestation and lactation is known to have adverse effects on offspring. We evaluate the impact of maternal diet on offspring bony labyrinth morphology. The bony labyrinth develops early and is thought to be stable to protect vital sensory organs within. For these reasons, bony labyrinth morphology has been used extensively to assess locomotion, hearing function, and phylogeny in primates and numerous other taxa. While variation related to these parameters has been documented, there is still a component of intraspecific variation that is unexplained. Although the labyrinthine developmental window is small, it may provide the opportunity for developmental instability to produce corresponding shape differences, as measured by fluctuating asymmetry (FA). We hypothesized that (a) offspring with poor maternal diet would exhibit increased FA, but (b) no unilateral shape difference. To test these hypotheses, we used two groups of rats (Rattus norvegicus; Crl:WI[Han] strain), one control group and one group exposed to a isocaloric, protein-restricted maternal diet during gestation and suckling. Individuals were sampled at weaning, sexual maturity, and old age. A Procrustes analysis of variance identified statistically significant FA in all diet-age subgroups. No differences in level of FA were identified among the subgroups, rejecting our first hypothesis. A principal components analysis identified no unilateral shape differences, supporting our second hypothesis. These results indicate that bony labyrinth morphology is remarkably stable and likely protected from a poor maternal diet during development. In light of this result, other factors must be explored to explain intraspecific variation in labyrinthine shape. 相似文献
33.
34.
In Vitro Differentiation and Expansion of Human Pluripotent Stem Cell-Derived Pancreatic Progenitors
Recent progress in understanding stem cell biology has been remarkable, especially in deciphering signals that support differentiation towards tissue-specific lineages. This achievement positions us firmly at the beginning of an era of patient-specific regenerative medicine and human disease modeling. It will be necessary to equip the progress in this era with a reliable source of self-renewing progenitor cells that differentiate into functional target cells. The generation of pancreatic progenitors that mature in vivo into functional beta-cells has raised the hope for new therapeutic options in diabetes, but key challenges still remain including the production of sufficient numbers of cells for research and transplantation. Recent approaches to this problem have shown that the presence of organ- and stage-specific mesenchyme improves the generation of progenitors, from endoderm to endocrine cells. Alternatively, utilization of three-dimensional culture may improve the efficiency and yield of directed differentiation. Here, we review the current knowledge of pancreatic directed differentiation and ex vivo expansion of pancreatic progenitors, including recent advances in differentiation strategies for the generation of pancreatic progenitors, and we discuss persistent challenges which will need to be overcome before personalized cell-based therapy becomes a practical strategy. 相似文献
35.
36.
Lorenzo Azzi Michele Cerati Maurizio Lombardo Maria Pellilli Fabio Croveri Vittorio Maurino Angelo Tagliabue Lucia Tettamanti Malgorzata Olszewska 《Oral diseases》2019,25(6):1465-1491
Chronic ulcerative stomatitis (CUS) is an immune‐mediated disorder characterized by oral erosions and ulcers usually refractory to conventional treatments. The disease often involves middle‐aged and older women with painful lesions sometimes resembling those of erosive oral lichen planus (OLP). The most affected sites are the buccal mucosa, the gingiva and the tongue, but the skin is involved in 22.5% of cases. Histopathologic features in CUS are non‐specific and indistinguishable from those of OLP, with the exception of the presence of a mixed infiltrate composed of lymphocytes and plasma cells. Direct immunofluorescence (DIF) analysis reveals the presence of stratified epithelium‐specific antinuclear antibodies (SES‐ANA) in the lower third of the epithelium. The IgG antibodies detected on DIF are directed against the ?Np63α isoform of p63 expressed in the nuclei of the epithelial basal cells. A distinguishing feature of CUS is the low response to conventional corticosteroid therapy and the good outcome with hydroxychloroquine at the dosage of 200 mg/day or higher dosages. This paper presents a comprehensive review of CUS and is accompanied by a new case report (the 73rd case) and a proposal for updated diagnostic criteria. 相似文献
37.
38.
Krzystek-Korpacka M Diakowska D Grabowski K Gamian A 《International journal of colorectal disease》2012,27(10):1319-1324
Purpose
The purpose of this study was to evaluate midkine, multipotential cytokine, and growth factor in colorectal cancer (CRC) stratified by tumor location.Methods
Midkine was assessed immunoenzymatically in paired cancerous and noncancerous tissues from 53 CRCs and referred to CRC stage, tumor location, and size, and circulating cytokine levels.Results
Midkine was higher in cancerous versus noncancerous tissue in 98?% cases (424.2 vs. 31.1?pg/mg, p?0.0001). Mean fold increase was 30.1; in 72.5?%, the relative increase was over fivefold. Midkine upregulation was more pronounced in colon than in rectum (fold increase: 36.6 vs. 12.7, p?=?0.005) due to higher midkine level in noncancerous rectal than colonic tissue (45.5 vs. 26.2?pg/mg, p?=?0.074). Tumor location affected midkine association with CRC stage. Midkine fold change was higher in advanced stages of rectal cancers (16.8 vs. 5.3, respectively in III/IV vs. I/II, p?=?0.013), while it tended to be lower in colonic ones (25.3 vs. 47.8, p?=?0.134). In addition, fold change in midkine level was higher in rectal N1 than N0 cancers (17.3 vs. 16.5, p?=?0.032), while it tended to be lower in colonic cancers (23.6 vs. 50.1, p?=?0.085). Midkine negatively correlated with tumor size (r?=?0.40, p?=?0.017), while it tended to positively correlate with its serum levels (r?=?0.45, p?=?0.081).Conclusions
Midkine is differently expressed in tumors arising from colonic and rectal mucosa, where it may play diverse roles in carcinogenesis. High midkine expression in noncancerous rectal mucosa might contribute to, a characteristic for rectal cancers, higher incidence of local recurrence. Divergent expression of midkine and its association pattern ought to be taken into account while designing midkine-directed therapies for CRC. 相似文献39.
40.
Wojcik M Dolezal-Oltarzewska K Janus D Drozdz D Sztefko K Starzyk JB 《Clinical endocrinology》2012,77(4):537-540
Fibroblast growth factor‐23 (FGF23) is a hormonal regulator of circulating phosphate and vitamin D levels. Recent investigations revealed that besides a key role in the pathogenesis of calcium–phosphorus disorders, in some patients FGF23 may be an indicator of cardiovascular complications. As a ‘hormone‐like’ factor, it may also be involved in some metabolic processes, especially in the metabolism of glucose and fat. Its potential contribution to metabolic syndrome (MS) development has not been confirmed yet. Objective The study was to examine the possible correlations between FGF23 serum levels and body composition, blood pressure and selected parameters of glucose, insulin and fat metabolism in adolescents with simple obesity. Patients and design In 68 (35 female) adolescents (mean age 13·9 years) with simple obesity [mean BMI SDS 4·9 (95% CI 4·4–5·4)], the levels of FGF23, total cholesterol, low‐density lipoprotein cholesterol, high‐density lipoprotein cholesterol and triglycerides were measured. Standard oral glucose tolerance tests were performed with the assessment of fasting and after 120′ postload glucose and insulin levels; the insulin resistance index HOMA‐IR was calculated. Results Regardless of gender, there was a significant inverse correlation between FGF23 and fasting insulin level (r = ?0·3), as well as HOMA‐IR (r = ?0·29). Multiple regression model showed the independent association between FGF23 and HOMA‐IR. Conclusion FGF23 seems to be a novel factor contributing to insulin sensitivity. Further investigations are needed to define its role in the development of MS. 相似文献