Project description:Despite the recent application of single-cell RNA-sequencing to aspects of mouse skin biology, the full cellular heterogeneity of the mouse skin (including both epidermis and skin stroma) and its relationship with the hair cycle is still uncharted. In order to systematically compare the cellular composition of mouse skin during rest and hair growth, we created single-cell RNA-sequencing libraries from full thickness mouse skin cell suspensions sampled during anagen (5w) and telogen (9w).
Project description:PPARgamma null (PpargΔ/Δ) mice present a generalized lipoatrophy and a dramatic skin phenotype, characterized by delayed hair morphogensis and the appearance, at adult age, of severe inflammatory infiltration. To investigate the molecular mechanisms underlying the delayed hair morphogenesis observed in PpargΔ/Δ mice, we used microarrays to detail the global program of gene expression in full thickness skin of PpargΔ/Δ mice and respective control mice at embryionic stage E17.5.
Project description:Hair follicles undergo recurrent cycling of controlled growth (anagen), regression (catagen), and relative quiescence (telogen) with a defined periodicity. Taking a genomics approach to study gene expression during synchronized mouse hair follicle cycling, we discovered that, in addition to circadian fluctuation, CLOCK-regulated genes are also modulated in phase with the hair growth cycle. During telogen and early anagen, circadian clock genes are prominently expressed in the secondary hair germ, which contains precursor cells for the growing follicle. Analysis of Clock and Bmal1 mutant mice reveals a delay in anagen progression, and the secondary hair germ cells show decreased levels of phosphorylated Rb and lack mitotic cells, suggesting that circadian clock genes regulate anagen progression via their effect on the cell cycle. Consistent with a block at the G1 phase of the cell cycle, we show a significant upregulation of p21 in Bmal1 mutant skin. While circadian clock mechanisms have been implicated in a variety of diurnal biological processes, our findings indicate that circadian clock genes may be utilized to modulate the progression of non-diurnal cyclic processes. To investigate the molecular control of hair follicle cycling, we profiled mRNA expression in mouse dorsal skin at multiple representative time points in the synchronized second postnatal hair growth cycle and in a depilation-induced hair growth cycle. For profiling of second synchronized and depilation-induced hair growth cycle, the same upper-mid region of dorsal skin was excised from C57BL/6 mice at representative postnatal days (P). The time points for second hair growth cycle are classified into different phases of the hair growth cycle based on established morphological guidelines as follow: early anagen (P23, P25), mid anagen (P27), late anagen (P29, P34), early catagen (P37, P39), mid catagen (P41), and telogen (P44). Depilation-induced hair growth cycle by applying wax/rosin mixture on the dorsal skin of seven-week old mice (all follicles in telogen) was performed on mice. The corresponding phases of the hair growth cycle at number of days following depilation (D) is as follow: early anagen (D3), mid anagen (D5), late anagen (D8, D12), and early catagen (D17). For each time point, multiple biological replicates were profiled, with each mouse dorsal skin separately hybridized to an Affymetrix array.
Project description:Among advanced resection techniques, endoscopic full thickness resection (EFTR) allows closure and full-thickness resection by the use of the non-exposed full thickness resection device (FTRD). The study is a retrospective analysis of technical failure occurring during colorectal full-thickness resection. Full thickness resection is a safe and effective procedure for "difficult" colorectal lesions. However, technical failure can occur and to date there is no evidence about type and clinical consequences in this setting.
Project description:Observational prospective multicenter study to investigate efficacy and safety of endoscopic full thickness resection in the lower GI tract using a novel over-the-scope full thickness resection device.
Project description:Hair follicles undergo recurrent cycling of controlled growth (anagen), regression (catagen), and relative quiescence (telogen) with a defined periodicity. Taking a genomics approach to study gene expression during synchronized mouse hair follicle cycling, we discovered that, in addition to circadian fluctuation, CLOCK-regulated genes are also modulated in phase with the hair growth cycle. During telogen and early anagen, circadian clock genes are prominently expressed in the secondary hair germ, which contains precursor cells for the growing follicle. Analysis of Clock and Bmal1 mutant mice reveals a delay in anagen progression, and the secondary hair germ cells show decreased levels of phosphorylated Rb and lack mitotic cells, suggesting that circadian clock genes regulate anagen progression via their effect on the cell cycle. Consistent with a block at the G1 phase of the cell cycle, we show a significant upregulation of p21 in Bmal1 mutant skin. While circadian clock mechanisms have been implicated in a variety of diurnal biological processes, our findings indicate that circadian clock genes may be utilized to modulate the progression of non-diurnal cyclic processes.
Project description:In this study, the skin tissues were harvested from the three stages of hair follicle cycling (anagen, catagen and telogen) in a fiber-producing goat breed. In total, 63,109,004 raw reads were obtained by Solexa sequencing and 61,125,752 clean reads remained for the small RNA digitalization analysis. This resulted in the identification of 399 conserved miRNAs; among these, 326 miRNAs were expressed in all three follicular cycling stages, whereas 3, 12 and 11 miRNAs were specifically expressed in anagen, catagen, and telogen, respectively. We also identified 172 potential novel miRNAs by Mireap, 36 miRNAs were expressed in all three cycling stages, whereas 23, 29 and 44 miRNAs were specifically expressed in anagen, catagen, and telogen, respectively. Gene Ontology and KEGG pathway analyses indicated that five major biological pathways (Metabolic pathways, Pathways in cancer, MAPK signalling pathway, Endocytosis and Focal adhesion) accounting for 23.08% of target genes among 278 biological functions, indicating that these pathways are likely to play significant roles during hair cycling. the skin tissues were harvested from the three stages of hair follicle cycling (anagen, catagen and telogen) in a fiber-producing goat breed
Project description:Keratin 1 (KRT1) and its heterodimer partner keratin 10 (KRT10) constitute the intermediate filament cytoskeleton of suprabasal skin keratinocytes. They participate in formation of the epidermal barrier, which protects against dehydration and inflammation. Mutations in KRT1 cause keratinopathic ichthyosis with erythema, recurrent inflammation, and barrier defects. Here, we show that genetic deletion of Krt1 in mice causes a defective inside-out epidermal barrier, pre- and postnatal increases in Mrp8/Mrp14, interleukin (IL) 18, IL-33, and thymic stromal lymphopoietin (TSLP) in skin extracts, and systemic release of IL-18 into newborn serum. Perinatal lethality was partially rescued by treatment with glucocorticoids to promote barrier repair or with IL- 18-blocking antibodies in utero. In human keratinocytes, IL-18 release was cellautonomous and caspase-1-dependent, indicating KRT1-dependent inflammasome activation. Our data reveal a novl function of KRT1 in controlling inflammasome activity and stimulating barrier formation, thereby integrating the keratin cytoskeleton into the epidermal immune response. In view of their widespread expression, keratins merit investigation of their functions in inflammatory conditions, including asthma and inflammatory bowel disorders. Total RNA was obtained from epidermis or full-thickness skin of Krt1+/+ and Krt1-/- mice (C57BL/6 background) at P0 (newborn).
Project description:Hair follicles undergo recurrent cycling of controlled growth (anagen), regression (catagen), and relative quiescence (telogen) with a defined periodicity. Taking a genomics approach to study gene expression during synchronized mouse hair follicle cycling, we discovered that, in addition to circadian fluctuation, CLOCK-regulated genes are also modulated in phase with the hair growth cycle. During telogen and early anagen, circadian clock genes are prominently expressed in the secondary hair germ, which contains precursor cells for the growing follicle. Analysis of Clock and Bmal1 mutant mice reveals a delay in anagen progression, and the secondary hair germ cells show decreased levels of phosphorylated Rb and lack mitotic cells, suggesting that circadian clock genes regulate anagen progression via their effect on the cell cycle. Consistent with a block at the G1 phase of the cell cycle, we show a significant upregulation of p21 in Bmal1 mutant skin. While circadian clock mechanisms have been implicated in a variety of diurnal biological processes, our findings indicate that circadian clock genes may be utilized to modulate the progression of non-diurnal cyclic processes. To gain molecular understanding of the the hair cycle delay in Clock mutant mice, we profiled the dorsal skin of Clock mutant and their wild-type littermates at P23. At P23, the skin samples are comparable because all the samples are in telogen just prior to the hair cycle delay was observed. Histological sections were used to classify each sample into specific stage of the hair growth cycle based on established morphological guidelines. RNA from each mouse dorsal skin were separately hybridized to an Affymetrix array.
Project description:Hair follicles undergo recurrent cycling of controlled growth (anagen), regression (catagen), and relative quiescence (telogen) with a defined periodicity. Taking a genomics approach to study gene expression during synchronized mouse hair follicle cycling, we discovered that, in addition to circadian fluctuation, CLOCK-regulated genes are also modulated in phase with the hair growth cycle. During telogen and early anagen, circadian clock genes are prominently expressed in the secondary hair germ, which contains precursor cells for the growing follicle. Analysis of Clock and Bmal1 mutant mice reveals a delay in anagen progression, and the secondary hair germ cells show decreased levels of phosphorylated Rb and lack mitotic cells, suggesting that circadian clock genes regulate anagen progression via their effect on the cell cycle. Consistent with a block at the G1 phase of the cell cycle, we show a significant upregulation of p21 in Bmal1 mutant skin. While circadian clock mechanisms have been implicated in a variety of diurnal biological processes, our findings indicate that circadian clock genes may be utilized to modulate the progression of non-diurnal cyclic processes. To gain molecular understanding of the the hair cycle delay in Bmal mutant mice, we profiled the dorsal skin of Bmal knockout (-/-) and their heterozygous (+/-) littermates at P22. At P22, the skin samples are comparable because all the samples are in telogen just prior to the hair cycle delay was observed. Histological sections were used to classify each sample into specific stage of the hair growth cycle based on established morphological guidelines. RNA from each mouse dorsal skin were separately hybridized to an Affymetrix Mouse Gene 1.0 ST array.