Matous, Pavel*
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BACKGROUND: The importance of membrane compartmentalization into specific membrane microdomains has been shown in many biological processes such as immunoreceptor signaling, membrane trafficking, pathogen infection, and tumor progression. Microdomains like lipid rafts, caveolae and tetraspanin enriched microdomains are relatively resistant to solubilization by some detergents. Large detergent-resistant membrane fragments (DRMs) resulting from such membrane solubilization can be conveniently isolated by density gradient ultracentrifugation or gel filtration. Recently, we described a novel type of raft-like membrane microdomains producing, upon detergent Brij98 solubilization, "heavy DRMs" and containing a number of functionally relevant proteins. Transmembrane adaptor protein LAX is a typical "heavy raft" protein. The present study was designed to identify the molecular determinants targeting LAX-derived constructs to heavy rafts. METHODOLOGY/PRINCIPAL FINDINGS: We prepared several constructs encoding chimeric proteins containing various informative segments of the LAX sequence and evaluated their effects on targeting to heavy rafts. Replacement of the polybasic membrane-proximal part of LAX by CD3ε-derived membrane-proximal part had no effect on LAX solubilization. Similarly, the membrane-proximal part of LAX, when introduced into non-raft protein CD25 did not change CD25 detergent solubility. These results indicated that membrane-proximal part of LAX is not important for LAX targeting to heavy rafts. On the other hand, the replacement of transmembrane part of CD25 by the transmembrane part of LAX resulted in targeting into heavy rafts. We also show that LAX is not S-acylated, thus palmitoylation is not involved in LAX targeting to heavy rafts. Also, covalent dimerization was excluded as a cause of targeting into heavy rafts. CONCLUSIONS/SIGNIFICANCE: We identified the transmembrane domain of LAX as a first motif targeting transmembrane protein constructs to detergent-resistant heavy rafts, a novel type of membrane microdomains containing a number of physiologically important proteins.
- MeSH
- adaptorové proteiny vezikulární transportní chemie genetika metabolismus MeSH
- buněčné linie MeSH
- interakční proteinové domény a motivy MeSH
- lidé MeSH
- membránové mikrodomény genetika metabolismus MeSH
- multimerizace proteinu MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Although keratin hydrolysates have become established as standard components in hair and nail cosmetics, studies on the moisturizing effects of keratin hydrolysates do not appear among contemporary literature. OBJECTIVES: To test if adding keratin hydrolysate into an ointment base increases hydration of the skin and improves skin barrier function, or diminishes trans-epidermal water loss. METHODS: Formulations were prepared containing 2%, 4%, and 6% keratin hydrolysates (based on weight of the ointment base). The moisturizing properties of keratin hydrolysates were tested by measuring skin hydration, trans-epidermal water loss and skin pH; measurements were carried out at intervals of 1, 2, 3, 4, 24, and 48 h. Testing was conducted on 10 women. RESULTS: As regards hydration, adding 2% keratin hydrolysate to the ointment base is optimal, as an increase of 14%-23% occurs in hydration of the stratum corneum. For trans-epidermal water loss, adding 4% KH to the ointment base is preferential, as this triggers a 26%-46% decrease in trans-epidermal water loss. CONCLUSIONS: Keratin hydrolysate acts as a humectant (it binds water from lower layers of the epidermis to the stratum corneum) as well as an occlusive (it reduces trans-epidermal water loss). The highly favorable properties of keratin hydrolysates are attributed to the wide distribution of keratin hydrolysates molecular weights; low-molecular weight fractions easily penetrate the SC, while high-molecular weight fractions form a protective film on the epidermis. Adding keratin hydrolysates to the ointment base did not cause phase separation even after 6 mo storage.
- MeSH
- dospělí MeSH
- epidermis chemie účinky léků fyziologie MeSH
- fyziologie kůže účinky léků MeSH
- hygroskopické látky farmakologie MeSH
- keratiny farmakologie MeSH
- koncentrace vodíkových iontů MeSH
- kosmetické přípravky farmakologie MeSH
- lidé MeSH
- masti MeSH
- perspiratio insensibilis účinky léků MeSH
- proteinové hydrolyzáty farmakologie MeSH
- voda metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
AIM: To evaluate the expression of epithelial markers of colorectal carcinogenesis in patients with long-term ulcerative colitis (UC) and primary sclerosing cholangitis (PSC) before and after transplantation. METHODS: Eight patients with UC and PSC prior to liver transplantation (PSC-UC), 22 patients with UC after liver transplantation for PSC (OLT), 9 patients with active ulcerative colitis without PSC (UCA), 7 patients with UC in remission (UCR) and 10 controls (N) underwent colonoscopy with multiple biopsies. Specimens were analysed histologically and semi-quantitatively immunohistochemically for p53, Bcl-2 and cyclooxygenase-2 (COX-2) markers. Statistical analysis was performed by Kruskal-Wallis and Fisher's exact tests. RESULTS: PSC-UC had a statistically significantly higher expression of p53 in the nondysplastic mucosa as compared to OLT, UCA, UCR and N (P < 0.05). We also found a statistically significant positive correlation between the incidence of PSC and the expression of p53 (P < 0.001). UCA had a higher p53 expression as compared to UCR. OLT had a significantly lower expression of p53 as compared with PSC-UC (P < 0.001). Bcl-2 had a significant higher bcl-2 expression as compared with controls. No difference in COX-2 expression between PSC-UC, UCR and UCA was found. UCA had higher COX-2 expression as compared to UCR. We also found a statistically significant positive correlation between the expression of COX-2 and p53. Patients after liver transplantation for PSC had a statistically significantly lower expression of the p53 compared with PSC-UC (P < 0.001). PSC-UC had the same inflammatory endoscopic activity as OLT and UCR when evaluated with the Mayo score. CONCLUSION: Our study shows that the nondysplatic mucosa of UC patients with PSC is characterised by a higher expression of the tumour suppressor gene p53, suggesting a higher susceptibility of cancer. This p53 overexpression correlates with the presence of PSC whilst it is not present in patients with UC after liver transplantation for PSC.
- MeSH
- biopsie MeSH
- cyklooxygenasa 2 analýza MeSH
- dospělí MeSH
- imunohistochemie MeSH
- kolonoskopie MeSH
- kolorektální nádory chemie etiologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- nádorové biomarkery analýza MeSH
- nádorový supresorový protein p53 analýza MeSH
- protoonkogenní proteiny c-bcl-2 analýza MeSH
- senioři MeSH
- sklerozující cholangitida etiologie metabolismus chirurgie MeSH
- studie případů a kontrol MeSH
- transplantace jater MeSH
- ulcerózní kolitida komplikace metabolismus chirurgie MeSH
- upregulace MeSH
- výsledek terapie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
... LINIE 37 -- Matouš Rous a ESKALACE LÉČBY RELAPS-REMITENTNÍ FORMY ROZTROUŠENÉ SKLERÓZY Z DIMETHYL FUMARÁTU ...
42 stran : ilustrace, tabulky ; 27 cm
- MeSH
- dimethyl fumarát MeSH
- roztroušená skleróza MeSH
- Publikační typ
- sborníky MeSH
- Konspekt
- Patologie. Klinická medicína
- NLK Obory
- neurologie
