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101.
Two new sesterterpene metabolites, 16-acetoxy-dihydrodeoxoscalarin (1) and astakolactin (2), were isolated from the sponge Cacospongia scalaris, collected from the gulf of Astakos, Greece, along with furoscalarol (3) and deoxoscalarin (4), which have not been reported from C. scalaris in the past. The unpalatability of the sponge to fish was traced by field feeding assays to the fractions containing dihydrofurospongin-2. The structures of the new metabolites were elucidated by interpretation of their NMR data and high-resolution mass spectral measurements. 相似文献
102.
Smyrniotopoulos V Abatis D Tziveleka LA Tsitsimpikou C Roussis V Loukis A Vagias C 《Journal of natural products》2003,66(1):21-24
Sixteen secondary metabolites of the green alga Caulerpa prolifera have been isolated, and their chemical structures elucidated by analysis of their spectroscopic data. Two groups of metabolites have been established, with either a 1,2-dihydro- (2a-2i) or a 1,2,3,3'-tetrahydro-2,3-didehydro (3a-3f) caulerpenyne carbon backbone. The terminal vinyl acetoxy group of caulerpenyne was substituted by various fatty acid residues. The antifouling activity of the algal extract was tested in laboratory assays against two of the major groups of fouling organisms (bacteria, microalgae). 相似文献
103.
A medical school was founded in Constantinople in 1827. Greek medics were involved with the new school right from its foundation, mainly because they had studied in Europe and knew other European and Asian languages. This paper reviews the lives of five of them: Stefanos Caratheodory; Constantinos Caratheodory; Sarantis Archigenis; Spyridon Mavrogenis; and Marco Pitsipio (Apostolidi Pasha), who was appointed a director of the Medical School. A few of the other Greek professors are also briefly discussed. 相似文献
104.
Chroni E Thomopoulos C Papapetropoulos S Paschalis C Karatza CL 《Journal of neurovirology》2003,9(3):408-410
A patient with two episodes of acute polyradiculoneuropathy (Guillain-Barré syndrome) that both occurred during exacerbation of chronic hepatitis B and separated by a 2-year asymptomatic interval is described. The possible causative relation between the neuropathy and the chronic hepatitis B is discussed. 相似文献
105.
Karapantzos I Tsaroucha A Polychronidis A Simopoulos C Simasko N 《ORL; journal for oto-rhino-laryngology and its related specialties》2003,65(6):370-374
Merkel cell carcinoma (MCC) is an infrequent, highly malignant, primary skin tumor derived from neuroendocrine cells. Most MCCs occur in elderly individuals, on sun-exposed areas of the body, with the head and neck being the most common sites. We present 7 patients (2 male and 5 female, age 45-80 years) suffering from MCC and treated between 1993 and 2000. All tumors were located on the head and neck and varied from 0.9 to 2.3 cm in size. Five of the patients had stage II disease, 1 patient had stage Ia disease and 1 patient had stage III disease. Six of the patients had positive regional lymph nodes. All patients had local excision of the tumor. Six of them also had lymph node dissection and in 5 of them a superficial parotidectomy was performed. Five patients received adjuvant radiotherapy and 3 of them also received chemotherapy. Local and cervical lymph node recurrence was observed in only 1 patient. Metastases occurred in 5 patients. One patient died within 10 days for other reasons. The patient with the stage III tumor had a survival of 7 months. The other 5 patients had survivals varying from 15 to 54 months. MCC is a skin tumor with very poor prognosis and high recurrence and metastatic rates. Its treatment is still under discussion. Radical excision of the tumor is the main method of treatment. Selective lymph node dissection is suggested. Superficial parotidectomy seems necessary, especially if the tumor is on the auricle. Adjuvant radio- and chemotherapy may extend survival in case of small-size tumors. 相似文献
106.
Antoniades C Demosthenous M Tousoulis D Antonopoulos AS Vlachopoulos C Toutouza M Marinou K Bakogiannis C Mavragani K Lazaros G Koumallos N Triantafyllou C Lymperiadis D Koutsilieris M Stefanadis C 《Hypertension》2011,58(1):93-98
We explored the role of asymmetrical dimethylarginine (ADMA) as a cause of endothelial dysfunction induced by systemic inflammation. In vitro data suggest that ADMA bioavailability is regulated by proinflammatory stimuli, but it is unclear whether ADMA is a link between inflammation and endothelial dysfunction in humans. In study 1 we recruited 351 patients with coronary artery disease (CAD) and 87 healthy controls. In study 2 we recruited 69 CAD, 69 healthy, and 10 patients with rheumatoid arthritis, whereas in study 3, 22 healthy and 70 CAD subjects were randomly assigned to Salmonella typhii vaccination (n=11 healthy and n=60 CAD) or placebo (n=11 healthy and n=10 CAD). Circulating interleukin 6/ADMA and flow-mediated dilation (FMD) were measured at 0 and 8 hours. In study 1, ADMA was inversely correlated with FMD in healthy individuals and CAD patients (P<0.0001 for both). However, interleukin 6 was inversely correlated with FMD (P<0.0001) in healthy subjects but not in CAD patients. The positive correlation between ADMA and interleukin 6 was stronger in healthy (r=0.515; P<0.0001) compared with CAD (r=0.289; P=0.0001) subjects. In study 2, both patients with rheumatoid arthritis and CAD had higher interleukin 6 (P<0.0001) and ADMA (P=0.004) but lower FMD (P=0.001) versus healthy subjects. In study 3, vaccination increased interleukin 6 in healthy (P<0.001) and CAD (P<0.001) subjects. FMD was reduced in healthy subjects (P<0.05), but its reduction in CAD was borderline. Vaccination increased ADMA only in healthy subjects (P<0.001). Systemic, low-grade inflammation leads to increased ADMA that may induce endothelial dysfunction. This study demonstrated that ADMA may be a link between inflammation and endothelial dysfunction in humans. 相似文献
107.
Leto-Aikaterini Tziveleka Anna-Maria G Psarra Dimitris Tsiourvas Constantinos M Paleos 《Journal of controlled release》2007,117(1):137-146
Fourth generation poly(propylene imine) dendrimer has been completely or partially functionalized with guanidinium groups. In the second case, the remaining toxic primary amino groups of the dendrimers were reacted with propylene oxide affording the corresponding hydroxylated derivatives. Five derivatives have been prepared bearing 0, 6, 12, 24 or 32 guanidinium groups. These guanidinylated dendrimers were interacted with plasmid DNA affording the corresponding dendriplexes. The complexes were physicochemically characterized by dynamic light scattering, zeta-potential measurements and AFM, while the extent of complexation was evaluated by agarose gel electrophoresis. Furthermore, their transfection efficiency was assessed employing HEK 293 and COS-7 cell lines, while the serum effect was studied in HEK 293 cells. It was found that complete replacement of primary amino groups with the hydroxylated moieties resulted in complete loss of transfection efficiency. On the contrary, guanidinylation of the parent dendrimer resulted to significant enhancement of its transfection efficiency, this enhancement being dependent on the number of guanidinium groups per dendrimer, the cell line used and the presence or absence of FBS. The fully guanidinylated dendrimer exhibited the best transfection efficiency under all the conditions studied. This efficiency has been attributed to the enhanced penetrating ability of the guanidinylated dendrimers due to the accumulation of the guanidinium group at the dendrimeric surface. It was also found that the derivative with 12 guanidinium groups exhibited the lowest toxicity. The reduction of toxicity was apparently attributed to the decrease of the external primary amino groups coupled with the presence of hydroxylated moieties located at the dendrimeric surface. The functionalization strategy employed leads to dendrimeric derivatives that combine satisfactory transfection efficiency and cytotoxicity. 相似文献
108.
Hypermethylation of CpG islands in the promoter region of the p15INK4B gene in childhood acute leukaemia 总被引:1,自引:0,他引:1
Tsellou E Troungos C Moschovi M Athanasiadou-Piperopoulou F Polychronopoulou S Kosmidis H Kalmanti M Hatzakis A Dessypris N Kalofoutis A Petridou E 《European journal of cancer (Oxford, England : 1990)》2005,41(4):584-589
It has been reported that the cyclin-dependent kinase inhibitor (CDKI) gene p15INK4B is frequently inactivated by genetic alterations and may be responsible for various malignant tumours. Another way of inactivation of this CDKI is by hypermethylation of 5'CpG islands in the promoter region of the p15INK4B gene and this inactivation seems to be a frequent event in various haematological malignancies. In the present study, we investigated the methylation status of the p151NK4B gene to clarify its role in the pathogenesis of childhood acute myeloid (AML) and acute lymphoblastic leukaemia (ALL). The study included 23 cases of B-cell origin ALL, 13 cases of T-cell origin ALL, 32 cases of AML, and 10 apparently healthy controls. Hypermethylation was studied by methylation-specific polymerase chain reaction. Hypermethylation of the p15INK4B gene was more frequent in cases with T-cell origin ALL (46.2%), but similar among children with B-cell origin ALL (13.0%) and AML (18.8%). Hypermethylation of p15INK4B may be involved in the pathogenesis of T-cell origin ALL, but not in that of AML or B-cell origin ALL. 相似文献
109.
High-frequency and medium-frequency components of different inspiratory nerve discharges and their modification by various inputs 总被引:1,自引:0,他引:1
Morton I. Cohen Wolf R. See Constantinos N. Christakos Anthony L. Sica 《Brain research》1987,417(1):148-152
In decerebrate paralyzed cats, spectral analysis was performed on simultaneous recordings of efferent inspiratory nerves (phrenic, recurrent laryngeal, hypoglossal). Spectral peaks were present both in the high-frequency (HFO) range (50-100 Hz) and the medium-frequency (MFO) range (20-50 Hz). Different activities were coherent only in the HFO range, indicating that the HFOs arise in a common inspiratory pattern generator that drives the different motoneuron populations, whereas the MFOs are specific to different systems. 相似文献
110.
Alexandros D Cokkinos Stylianos Tzeis Panagiotis Moraitis Constantinos Pantos Hariklia Carageorgiou Dimitrios Panousopoulos Dennis D Varonos Dennis V Cokkinos 《Experimental & Clinical Cardiology》2003,8(1):5-9