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621.
Eleni?Douni Petros?P?Sfikakis Sylva?Haralambous Peter?Fernandes George?KolliasEmail author 《Arthritis research & therapy》2003,6(1):R65
The impact of diacerein, an effective cartilage targeted therapy that is used in patients with osteoarthritis, on the development
and progression of chronic inflammatory arthritis was evaluated in a tumor necrosis factor (TNF) transgenic mouse model (Tg197).
The response to diacerein at 2, 20, or 60 mg/kg daily, as well as the comparative effects of other antiarthritis drugs including
dexamethasone (0.5 mg/kg daily), methotrexate (1 mg/kg three times weekly) and an anti-TNF agent (5 mg/kg weekly), were assessed
in the Tg197 mice. Treatment was initiated before the onset of arthritis and was continued for 5 weeks. A significant improvement
in clinical symptoms was found in all three diacerein treated groups in comparison with untreated groups. Confirming these
data, semiquantitative histopathologic analysis of the hind paws revealed a significant reduction not only in cartilage destruction
but also in the extent of synovitis and bone erosion in diacerein treated groups in comparison with untreated groups. At the
most effective dose tested (2 mg/kg daily), diacerein inhibited the onset of arthritis in 28% and attenuated the progression
of arthritis in 35% of the Tg197 mice. Comparative analyses showed diacerein to be more potent than methotrexate but not as
effective as dexamethasone or anti-TNF agents in suppressing the progression of the TNF mediated arthritis in this model.
These results indicate that diacerein has a disease modifying effect on the onset and progression of TNF driven chronic inflammatory
arthritis, suggesting that the prophylactic or therapeutic potential of diacerein in patients with RA should be further examined. 相似文献
622.
Marc?StadlerEmail author Hans-Volker?Tichy Eleni?Katsiou Veronika?Hellwig 《Mycological Progress》2003,2(2):95-122
Pochonins are antiviral and antiparasitic resorcylic acid lactones (RAL) structurally related to monorden. They were found
in the invertebrate-associated fungus Pochonia chlamydosporia. Their production and distribution was studied by means of High Performance Liquid Chromatography with UV-visual and mass
spectrometric detection (HPLC-UV/Vis and HPLCMS) in cultures of Pochonia species and further conidial fungi with Verticillium-like anamorphs that had until recently been included in Verticillium sect. Prostrata. The results support the recent generic segregation by Gams, Zare and co-workers because pochonins were found to occur exclusively
in species of the genus Pochonia. With few exceptions, the production of RAL appeared to be a rather constant feature in cultures of P. chlamydosporia from around the world. According to preliminary results, secondary metabolite profiles in strains of allied genera such as
Lecanicillium, Haptocillium and Rotiferophthora are different from those encountered in Pochonia. The alkaloid pseurotin A was found as main metabolite in several of the P. chlamydosporia isolates examined. As inferred from HPLC profiling data, strains of P. suchlasporia clustered into at least three chemotypes. The ex-type strain of P. suchlasporia var. catenata produced monorden, while several other strains produced metabolites whose HPLC-UV and HPLC-MS characteristics were similar
to the mycotoxins, aurovertin B and citreoviridin A. Yet different metabolites were detected in a third chemotype of P. suchlasporia. Differences in secondary metabolite profiles were also found in two strains of P. bulbillosa. While the ex-type strain was found devoid of all aforementioned compounds, CBS 247.68 contained the aurovertin-related metabolites
detected in part of the P. suchlasporia isolates. The sequence of the ITS nrDNA of CBS 247.68 was different from that of the type strain but identical to the sequences
of P. suchlasporia var. catenata. Several strains of the latter variety showed identical sequences, despite considerable variations in their HPLC metabolite
profiles. Minisatellite PCR fingerprinting was found useful to segregate Pochonia at species and strain level, pointing toward the existence of further, cryptic species. The possible chemotaxonomical importance
and ecological functions of secondary metabolites in these fungi is discussed. 相似文献
623.
624.
Iliopoulos D Vassiliou G Sekerli E Sidiropoulou V Tsiga A Dimopoulou D Voyiatzis N 《Genetics and molecular research : GMR》2005,4(4):755-759
The live birth of a triploidy infant is a very rare event and death usually occurs within the first hours of life. Triploid cases with a survival of more than two months are infrequent. We report on an infant with a 69,XXX chromosome constitution who survived 164 days. Chromosomal analysis demonstrated a 69,XXX karyotype with no evidence of mosaicism. This is the longest survival reported for this condition to date in Greece and the fourth longest worldwide. The infant was admitted to our clinic several times due to respiratory problems, and supplementary oxygen was required. The improved survival of our case was possibly due to better management of respiratory illness and prematurity, and these are essential factors that physicians should consider carefully with such rare cases. 相似文献
625.
Scale-up production of puerarin from hairy roots of Pueraria phaseoloides in an airlift bioreactor 总被引:2,自引:0,他引:2
Kintzios S Makri O Pistola E Matakiadis T Shi HP Economou A 《Biotechnology letters》2004,26(13):1057-1059
Hairy roots of the Chinese herb, Pueraria phaseoloides, obtained from leaf explants and transformed with the Agrobacterium rhizogenes, were cultured in 2.5 l airlift bioreactors for three weeks. Puerarin accumulated at 5,570 microg g(-1) dry wt, which is near 200 times as much as in 250 ml flask cultures. In addition, puearin was exuded into the nutrient medium at final concentrations higher than in the hairy roots themselves. 相似文献
626.
Bone morphogenetic protein expression in newborn rat kidneys after prenatal exposure to radiofrequency radiation 总被引:1,自引:0,他引:1
Pyrpasopoulou A Kotoula V Cheva A Hytiroglou P Nikolakaki E Magras IN Xenos TD Tsiboukis TD Karkavelas G 《Bioelectromagnetics》2004,25(3):216-227
Effects of nonthermal radiofrequency radiation (RFR) of the global system of mobile communication (GSM) cellular phones have been as yet mostly studied at the molecular level in the context of cellular stress and proliferation, as well as neurotransmitter production and localization. In this study, a simulation model was designed for the exposure of pregnant rats to pulsed GSM-like RFR (9.4 GHz), based on the different resonant frequencies of man and rat. The power density applied was 5 microW/cm2, in order to avoid thermal electromagnetic effects as much as possible. Pregnant rats were exposed to RFR during days 1-3 postcoitum (p.c.) (embryogenesis, pre-implantation) and days 4-7 p.c. (early organogenesis, peri-implantation). Relative expression and localization of bone morphogenetic proteins (BMP) and their receptors (BMPR), members of a molecular family currently considered as major endocrine and autocrine morphogens and known to be involved in renal development, were investigated in newborn kidneys from RFR exposed and sham irradiated (control) rats. Semi-quantitative duplex RT-PCR for BMP-4, -7, BMPR-IA, -IB, and -II showed increased BMP-4 and BMPR-IA, and decreased BMPR-II relative expression in newborn kidneys. These changes were statistically significant for BMP-4, BMPR-IA, and -II after exposure on days 1-3 p.c. (P <.001 each), and for BMP-4 and BMPR-IA after exposure on days 4-7 p.c. (P <.001 and P =.005, respectively). Immunohistochemistry and in situ hybridization (ISH) showed aberrant expression and localization of these molecules at the histological level. Our findings suggest that GSM-like RFR interferes with gene expression during early gestation and results in aberrations of BMP expression in the newborn. These molecular changes do not appear to affect renal organogenesis and may reflect a delay in the development of this organ. The differences of relative BMP expression after different time periods of exposure indicate the importance of timing for GSM-like RFR effects on embryonic development. 相似文献
627.
Zannis VI Chroni A Kypreos KE Kan HY Cesar TB Zanni EE Kardassis D 《Current opinion in lipidology》2004,15(2):151-166
PURPOSE OF THE REVIEW: This review clarifies the functions of key proteins of the chylomicron and the HDL pathways. RECENT FINDINGS: Adenovirus-mediated gene transfer of several apolipoprotein (apo)E forms in mice showed that the amino-terminal 1-185 domain of apoE can direct receptor-mediated lipoprotein clearance in vivo. Clearance is mediated mainly by the LDL receptor. The carboxyl-terminal 261-299 domain of apoE induces hypertriglyceridemia, because of increased VLDL secretion, diminished lipolysis and inefficient VLDL clearance. Truncated apoE forms, including apoE2-202, have a dominant effect in remnant clearance and may have future therapeutic applications for the correction of remnant removal disorders. Permanent expression of apoE and apoA-I following adenoviral gene transfer protected mice from atherosclerosis. Functional assays, protein cross-linking, and adenovirus-mediated gene transfer of apoA-I mutants in apoA-I deficient mice showed that residues 220-231, as well as the central helices of apoA-I, participate in ATP-binding cassette transporter A1-mediated lipid efflux and HDL biogenesis. Following apoA-I gene transfer, an amino-terminal deletion mutant formed spherical alpha-HDL, a double amino- and carboxyl-terminal deletion mutant formed discoidal HDL, and a carboxyl-terminal deletion mutant formed only pre-beta-HDL. The findings support a model of cholesterol efflux that requires direct physical interactions between apoA-I and ATP-binding cassette transporter A1, and can explain Tangier disease and other HDL deficiencies. SUMMARY: New insights are provided into the role of apoE in cholesterol and triglyceride homeostasis, and of apoA-I in the biogenesis of HDL. Clearance of the lipoprotein remnants and increase in HDL synthesis are obvious targets for therapeutic interventions. 相似文献
628.
Drousiotou A Stylianidou G Anastasiadou V Christopoulos G Mavrikiou E Georgiou T Kalakoutis G Oladimeji A Hara Y Suzuki K Furihata K Ueno I Ioannou PA Fensom AH 《Human genetics》2000,107(1):12-17
In the last 15 years, four patients with the infantile form of Sandhoff disease were diagnosed in four different families in Cyprus (population 703,000, birth rate 1.7%). Three of these cases came from the Christian Maronite community (less than 1% of the population) and one from the Greek community (84% of the population). This relatively large number of patients prompted us to initiate an epidemiological study in order to establish the frequency of the mutant allele in Cyprus. Carrier detection was initially based on the measurement of beta-hexosaminidase A and B in both leucocytes and serum. Using the enzyme test, 35 carriers were identified among 244 random Maronite samples and 15 among 28 Maronites with a family history of Sandhoff disease, but only one carrier was found out of 115 random samples from the Greek community. In parallel to the biochemical screening, DNA studies were undertaken in one of the three Maronite patients and in a Greek carrier related to the Greek patient. These studies resulted in the identification of two novel mutations, a deletion of A at nt76 and a G to C transversion at position 5 of the 5'-splice site of intron 8, which have been published. We subsequently screened the carriers detected in the biochemical study for these two mutations using PCR-based tests. Of 50 Maronite carriers examined, 42 were found to have the nt76 deletion. Eight Maronite samples, designated carriers from the biochemical results, were negative for both mutations. It is possible that these individuals were incorrectly classified as carriers since their enzyme values are equivocal, although the presence of another mutation has not been excluded. Two Greek Cypriot carriers and two obligate Lebanese carriers were negative for both mutations. We conclude that there is a high frequency of Sandhoff disease carriers in the Maronite community of Cyprus, approximately 1 in 7, and that a single mutation predominates in this population. 相似文献
629.
630.
Josipa Vlainić Ivan Kosalec Kristina Pavić Dimitra Hadjipavlou-Litina Eleni Pontiki 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):376-382
Primaquine (PQ) ureidoamides 5a–f were screened for antimicrobial, biofilm eradication and antioxidative activities. Susceptibility of the tested microbial species towards tested compounds showed species- and compound-dependent activity. N-(diphenylmethyl)-2-[({4-[(6-methoxyquinolin-8-yl)amino]pentyl}carbamoyl)amino]-4-methylpentanamide (5a) and 2-(4-chlorophenyl)-N-(diphenylmethyl)-2-[({4-[(6-methoxyquinolin-8-yl)amino]pentyl}carbamoyl)amino]acetamide (5d) showed antibacterial activity against S. aureus strains (MIC?=?6.5?µg/ml). Further, compounds 5c and 5d had weak antibacterial activity against Escherichia coli and Pseudomonas aeruginosa. None of the tested compounds showed a wide spectrum of antifungal activity. In contrast, most of the compounds exerted strong activity in a biofilm eradication assay against E. coli, P. aeruginosa and Candida albicans, comparable to or even higher than gentamycin, amphotericin B or parent PQ. The most active compounds were 5a and 5b. Tested compounds were inactive against biofilm formation by C. parapsylosis, Enterococcus faecalis, C. tropicalis and C. krusei. Compounds 5b–f significantly inhibited lipid peroxidation (80–99%), whereas compound 5c presented interesting LOX inhibition. 相似文献