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101.
Pulmonary surfactant is a complex mixture of phospholipids and proteins, which is present in the alveolar lining fluid and is essential for normal lung function. Alterations in surfactant composition have been reported in several interstitial lung diseases (ILDs). Furthermore, a mutation in the surfactant protein C gene that results in complete absence of the protein has been shown to be associated with familial ILD. The role of surfactant in lung disease is therefore drawing increasing attention following the elucidation of the genetic basis underlying its surface expression and the proof of surfactant abnormalities in ILD.  相似文献   
102.
In the present work, the combination of chemical and enzymatic methods to obtain neoglycoproteins is described. Three bovine serum albumin (BSA)-conjugates, BSA-[GalNAc alpha-], BSA-[Gal(beta 1-3)GalNAc(alpha-], and BSA-[Neu5Ac(alpha 2-3)Gal(beta 1-3)GalNAc(alpha-], were prepared. alpha GalNAc derivatives were galactosylated employing crude beta-galactosidase from bovine testes. The use of oversaturated donor solutions (pNP beta Gal) enhanced the yields up to 60%. This method was verified using divalent structures as acceptors, that rendered di- and tri-galactosylated products. Further treatment of the disaccharides with CMP-Neu5Ac and alpha 2-3 sialyltransferase from pork liver led to formation of trisaccharides. Finally, mono-, di-, and trisaccharides were coupled to BSA employing a thiolic group introduced into the protein for Michael addition to a maleinimide group in the spacer-arm of the saccharide components. The results were monitored by HPLC and MALDI-TOF.  相似文献   
103.
Recent studies suggest the potential involvement of CD8+ T cells in the pathogenesis of murine hypertension. We recently reported that immunization with apoB-100 related peptide, p210, modified CD8+ T cell function in angiotensin II (AngII)-infused apoE (-/-) mice. In this study, we hypothesized that p210 vaccine modulates blood pressure in AngII-infused apoE (-/-) mice. Male apoE (-/-) mice were immunized with p210 vaccine and compared to unimmunized controls. At 10 weeks of age, mice were subcutaneously implanted with an osmotic pump which released AngII for 4 weeks. At 13 weeks of age, p210 immunized mice showed significantly lower blood pressure response to AngII compared to controls. CD8+ T cells from p210 immunized mice displayed a different phenotype compared to CD8+ T cells from unimmunized controls. Serum creatinine and urine albumin to creatinine ratio were significantly decreased in p210 immunized mice suggesting that p210 vaccine had renal protective effect. At euthanasia, inflammatory genes IL-6, TNF-α, and MCP-1 in renal tissue were down-regulated by p210 vaccine. Renal fibrosis and pro-fibrotic gene expression were also significantly reduced in p210 immunized mice. To assess the role of CD8+ T cells in these beneficial effects of p210 vaccine, CD8+ T cells were depleted by CD8 depleting antibody in p210 immunized mice. p210 immunized mice with CD8+ T cell depletion developed higher blood pressure compared to mice receiving isotype control. Depletion of CD8+ T cells also increased renal fibrotic gene expression compared to controls. We conclude that immunization with p210 vaccine attenuated AngII-induced hypertension and renal fibrosis. CD8+ T cells modulated by p210 vaccine could play an important role in the anti-hypertensive, anti-fibrotic and renal-protective effect of p210 vaccine.  相似文献   
104.
Myoepitheliomas of the extremity are rare and usually benign, while a minority display malignant features. This case demonstrates the diagnosis and management of myoepithelioma within the carpal tunnel. Clinical and radiological tumour features were evaluated. Hematoxylin and eosin stained tumour sections were examined, and immunohistochemistry was performed. Histology revealed a nodular mass of epithelioid cells in clusters within a myxoid/chondroid stroma. No mitoses were noted. Cytokeratins, neuron-specific enolase, synaptophysin, glial fibrillary acidic protein, and S100 were positive on immunohistochemistry. A literature review revealed very few prior reports of myoepithelioma in the wrist, and limited data concerning any relationship between recurrence and quality of surgical margins. In this case, wide local excision would have significantly compromised dominant hand function, and therefore a marginal excision was deemed appropriate in the context of bland histological features. Surgical margins noted in future case reports will aid clinical decision making.  相似文献   
105.

Introduction

Detection of (subclinical) synovitis is relevant for both early diagnosis and monitoring of therapy of rheumatoid arthritis (RA). Previously, the potential of imaging (sub)clinical arthritis was demonstrated by targeting the translocator protein in activated macrophages using (R)-[11C]PK11195 and positron emission tomography (PET). Images, however, also showed significant peri-articular background activity. The folate receptor (FR)-β is a potential alternative target for imaging activated macrophages. Therefore, the PET tracer [18F]fluoro-PEG-folate was synthesized and evaluated in both in vitro and ex vivo studies using a methylated BSA induced arthritis model.

Methods

[18F]fluoro-PEG-folate was synthesized in a two-step procedure. Relative binding affinities of non-radioactive fluoro-PEG-folate, folic acid and naturally circulating 5-methyltetrahydrofolate (5-Me-THF) to FR were determined using KB cells with high expression of FR. Both in vivo [18F]fluoro-PEG-folate PET and ex vivo tissue distribution studies were performed in arthritic and normal rats and results were compared with those of the established macrophage tracer (R)-[11C]PK11195.

Results

[18F]fluoro-PEG-folate was synthesized with a purity >97%, a yield of 300 to 1,700 MBq and a specific activity between 40 and 70 GBq/µmol. Relative in vitro binding affinity for FR of F-PEG-folate was 1.8-fold lower than that of folic acid, but 3-fold higher than that of 5-Me-THF. In the rat model, [18F]fluoro-PEG-folate uptake in arthritic knees was increased compared with both contralateral knees and knees of normal rats. Uptake in arthritic knees could be blocked by an excess of glucosamine-folate, consistent with [18F]fluoro-PEG-folate being specifically bound to FR. Arthritic knee-to-bone and arthritic knee-to-blood ratios of [18F]fluoro-PEG-folate were increased compared with those of (R)-[11C]PK11195. Reduction of 5-Me-THF levels in rat plasma to those mimicking human levels increased absolute [18F]fluoro-PEG-folate uptake in arthritic joints, but without improving target-to-background ratios.

Conclusions

The novel PET tracer [18F]fluoro-PEG-folate, designed to target FR on activated macrophages provided improved contrast in a rat model of arthritis compared with the accepted macrophage tracer (R)-[11C]PK11195. These results warrant further exploration of [18F]fluoro-PEG-folate as a putative PET tracer for imaging (sub)clinical arthritis in RA patients.  相似文献   
106.
P Bogani  A Simoni  P Lio  A Germinario  M Buiatti 《Génome》2001,44(4):549-558
Previous work has shown the fixation of context-specific random amplified polymorphic DNA (RAPD) patterns in tomato cell cultures grown for 2 years in different hormonal contexts. In this work, RAPD sequences were characterised and RAPD-derived molecular markers used for a further study of variation between and within auto- and auxo-trophic tomato cultures grown in different hormonal equilibria. Results were then compared with those obtained using microsatellite markers located in noncoding regions of differentiation- and hormone-related genes and with those obtained with the external transcribed spacer (ETS) from tomato rDNA. Hybridisation of RAPDs on a tomato genomic DNA bank, or on total DNA after enzymatic digestion, suggested that the markers were repetitive in nature. Sequence analysis. however, showed that the homology between different fragments was due mainly to the presence of homo-AT nucleotide stretches. Moreover, a series of computational methods, such as an information-theory algorithm coupled with AG estimates, suggested that the RAPD fragments isolated in our experiments are noncoding. The amplification of SSR-containing RAPD-derived markers, and of other SSRs located in noncoding regions of tomato functional genes, consistently showed polymorphism between auxo- and auto-trophic somaclones (the latter being either habituated or transgenic for Agrobacterium tumefaciens oncogenes) but not within these same clones. Differences were also found between auxotrophic clones and the differentiated tissue. These findings were confirmed by restriction fragment length polymorphism (RFLP) analysis with the REII repetitive element of the ETS from tomato rDNA, which was isolated during this study. The results obtained suggest a possible role for physiological context in the selection of RAPD patterns during the evolution of tomato cells with different endogenous hormonal equilibria. The results are discussed in terms of a possible role for variation in noncoding regions of hormone-related genes in the adaptation to different physiological contexts.  相似文献   
107.
The dual specificity phosphatase PTEN exerts its tumour suppressor and cell-migration regulatory functions by dephosphorylating the phospholipid substrate, phosphatidylinositol-3,4,5-trisphosphate (PI(3,4,5)P(3)), and phosphotyrosine protein substrates. PTEN functions are regulated by phospholipid binding, interactions with other cellular proteins and phosphorylation at multiple sites. Precisely, how the phosphorylation and binding events modulate PTEN activity and structure remains mostly unclear. Detailed studies of this issue require the availability of significant quantity of both the unphosphorylated and phosphorylated forms of purified recombinant PTEN. Here, we describe the successful expression and purification of recombinant rat PTEN using a baculovirus-infected Spodoptera frugiperda (Sf9) cell expression system. The recombinant PTEN was purified to near homogeneity using four sequential column chromatographic steps. The specific enzymatic activity of the purified preparation in dephosphorylating PI(3,4,5,)P(3) and the artificial phosphotyrosine substrate poly(Glu/Tyr) are 6.7 nmol/min/microg and 0.006 pmol/min/microg, respectively. Intriguingly, similar to PTEN expressed in mammalian cells, the recombinant PTEN was phosphorylated in the infected insect cells at Ser-380, Thr-382, and Thr-383 at the C-terminal tail. Treatment with alkaline phosphatase fully dephosphorylated these sites. After the treatment, the unphosphorylated PTEN and alkaline phosphatase could be separated by ion exchange column chromatography. The availability of the phosphorylated and unphosphorylated forms of recombinant PTEN permits future investigations into the three-dimensional structures of the phosphorylated and unphosphorylated forms of PTEN, and the role of phosphorylation in regulating PTEN activity, phospholipid- and protein-binding affinities.  相似文献   
108.

Background  

Relaxin is the endogenous ligand of the G-protein coupled receptor RXFP1, previously known as LGR7. In humans relaxin can also activate, but with lower affinity, the closely related receptor for the insulin-like peptide from Leydig cells, RXFP2, previously known as LGR8. The lack of relaxin impairs male fertility but the precise distribution and the function of relaxin receptors in the male reproductive tract is not known. We investigated the distribution of Rxfp1 and Rxfp2 in the reproductive tract of the male rat and the function of relaxin in the vas deferens, a tissue with high expression of both receptors.  相似文献   
109.
Cinnamic acid derivatives were prepared on Rink resin using tert-butyl-4-carboxycinnamate in a four-component Ugi condensation. Inhibition of the hematopoietic protein tyrosine phosphatase (HePTP) by these small molecules is reported. An IC50 value of 3.9 μM was determined for the most potent inhibitor discovered.  相似文献   
110.
In subjects affected by trisomy 21 (Down syndrome), hypothyroidism is the most common endocrinological deficit. Plasma zinc levels, which are commonly detected below the normal range in Down patients, are related to some endocrinological and immunological functions; in fact, zinc deficiency has been shown to impair immune response and growth rate. Aims of this study were to evaluate (1) the role of zinc deficiency in subclinical hypothyroidism and (2) thyroid function changes in Down children cyclically supplemented with zinc sulfate. Inverse correlations have been observed between age and triiodotironine (T3) and between zinc and thyroid-stimulating hormone (TSH); higher TSH levels have been found in hypozincemic patients at the beginning of the study. After 6 mo of supplementation, an improvement of thyroid function (TSH levels: 3.96 ± 1.84 vs 2.64 ± 1.33 mUI/mL basally and after 6 mo, respectively) was observed in hypozincemic patients. In the second cycle of supplementation, a similar trend of TSH was observed. At the end of the study, TSH significantly decreased in treated hypozincemic subjects (4.48 ± 1.93 vs 2.96 ± 1.20 mUI/mL) and it was no longer different in comparison to normozincemic patients. We suggest zinc supplementation to the diet in hypozincemic Down children as a simple and useful therapeutic tool.  相似文献   
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