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Nabila Brahmi-Chendouh Simona Piccolella Giuseppina Crescente Francesca Pacifico Lila Boulekbache Sabrina Hamri-Zeghichi Salah Akkal Khodir Madani Severina Pacifico 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2019,27(3):692-702
Nowadays, advanced extraction techniques and highly sensitive metabolic profiling methods are effectively employed to get new information on plant chemical constituents. Among them wild medicinal plants or their parts, with large and ancient use in folk medicine, are investigated for their potential functional use and cultivation. In this context, Inula viscosa leaves engaged our attention. A simple experimental design, based on Soxhlet extraction and chromatographic fractionation, allowed us to obtain the investigated polyphenol fraction (IvE). UHPLC-HRMS analyses revealed shikimoyl depsides of caffeic acid and unusual dihydrobenzofuran lignans as main secondary metabolites. These compounds, together with cinchonain-type phenols, and hydroxycinnamoyl flavonol glycosides, are reported for the first time in inula. Overall, forty-three secondary metabolites were identified. The extract exerted a remarkable antiradical activity towards DPPH? and ABTS+?. Furthermore, it was able to inhibit cell viability and mitochondrial redox activity of neuroblastoma, hepatoblastoma and colon carcinoma cells, whereas it did not affect cell density of HaCaT cells immortalized human keratinocytes. As detected by the oxidant-sensing probe 2′,7′-dichlorodihydrofluorescein diacetate, the inhibitory responses seemed to be related to IvE-induced increase of intracellular reactive oxygen species (ROS). The obtained results highlighted that inula leaves, nowadays even undervalued and unexplored, could be considered a renewable source of nutraceutical compounds. 相似文献
3.
This article describes early stages in the acquisition of a first vocabulary by infants and young children. It distinguishes two major stages, the first of which operates by a stand‐alone word‐to‐world pairing procedure and the second of which, using the evidence so acquired, builds a domain‐specific syntax‐sensitive structure‐to‐world pairing procedure. As we show, the first stage of learning is slow, restricted in character, and to some extent errorful, whereas the second procedure is determinative, rapid, and essentially errorless. Our central claim here is that the early, referentially based learning procedure succeeds at all because it is reined in by attention‐focusing properties of word‐to‐world timing and related indicants of referential intent. 相似文献
4.
Thyroid stimulating hormone (TSH) and prolactin (PRL) plasma levels were studied during electroconvulsive therapy (ECT) in five schizophrenic patients in a simulated ECT (SECT) controlled experimental design. The data were compared to those obtained from a group of 10 depressed patients treated with ECT. In the schizophrenic group, both PRL and TSH increased significantly during ECT compared to SECT, as they did in the depressive group during ECT. Thus, the hormonal TSH and PRL profile during ECT is similar in schizophrenia and depression. It is concluded that the changes in TSH and PRL induced by ECT are specifically linked to the current or the seizure, and are not related to the type of psychopathology. 相似文献
5.
Autoradiographic localization of beta-adrenoceptors in pig lung using [125I]-iodocyanopindolol. 总被引:1,自引:1,他引:0 下载免费PDF全文
R. G. Goldie J. M. Papadimitriou J. W. Paterson P. J. Rigby D. Spina 《British journal of pharmacology》1986,88(3):621-628
The binding of the beta-adrenoceptor radioligand [125I]-iodocyanopindolol (I-CYP) has been studied in pig lung parenchyma and the distribution of binding sites visualised by light microscopic autoradiography. I-CYP binding was saturable (maximum binding capacity Bmax = 51 +/- 3 fmol mg-1 protein), involving sites with high affinity (dissociation constant KD = 73 +/- 10 pM). Specific I-CYP binding was displaceable both by beta-adrenoceptor agonists ((-)-isoprenaline greater than (-)-adrenaline greater than (+/-)-fenoterol greater than (-)-noradrenaline greater than (+)-isoprenaline greater than (+/-)-RO363) and antagonists ((+/-)-propranolol greater than ICI-118551 greater than atenolol), indicating a predominance of beta 2-adrenoceptors. Further analysis showed that displacement data for the beta 1-selective antagonist atenolol and the beta 2-selective antagonist ICI-118551 were fitted best to a 2 binding site model and that both beta 1- and beta 2-adrenoceptors were present in pig lung in the ratio 28:72 respectively. Autoradiographic grains were localized over tissue and were most dense over alveolar walls greater than vascular endothelium greater than vascular smooth muscle greater than bronchial smooth muscle = bronchial epithelium. Atenolol (10(-5) M) caused a 31% reduction in specific grain density over alveolar wall tissue, while a 10 fold lower concentration of ICI-118551 (10(-6) M) caused a 50% decrease. These results are consistent with binding data in pig lung parenchyma demonstrating a mixed population of beta-adrenoceptors with a predominance of the beta 2 subtype.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
A murine cytomegalovirus-neutralizing monoclonal antibody exhibits autoreactivity and induces tissue damage in vivo. 下载免费PDF全文
A J Chapman H E Farrell J A Thomas J M Papadimitriou M J Garlepp A A Scalzo G R Shellam 《Immunology》1994,81(3):435-443
The autoreactivity of murine cytomegalovirus (MCMV)-neutralizing monoclonal antibody (mAb) AC1 was examined in vitro and in vivo. Both mAb AC1 and a human antiserum reactive with U1-small nuclear ribonucleoprotein (U1-snRNP) stained uninfected mouse embryo fibroblasts (MEF) in a speckled nuclear pattern and reacted with 70,000 molecular weight (MW) MEF nuclear antigens by immunoblotting, suggesting that mAb AC1 cross-reacted with the 70,000 MW component of U1-snRNP. However, only mAb AC1 cross-reacted with an additional epithelial cytoplasmic autoantigen present in cultured HEp2 cells. On tissue sections from uninfected mice, mAb AC1 predominantly reacted with a component of central and peripheral nervous systems, although cross-reactivity with the stratum spinosum of the skin and the outer sheath of hair follicles was also observed. Immunoblotting revealed that mAb AC1 reacted with phosphorylated epitopes present on a 98,000 MW MCMV structural protein and the 200,000 MW mouse neurofilament protein (NFP). Treatment of uninfected mice with mAb AC1 resulted in a severe interstitial pneumonia with greatly thickened and congested alveolar septa. Severe oedema of the hypodermis and a mild mesangial proliferative glomerulonephritis were also observed. These results demonstrate that a mAb reacting with a MCMV structural phosphoprotein which can protect mice against the dissemination of MCMV, can also promote the development of autoimmune disease. Therefore, the production of such cross-reactive antibodies may be an important mechanism in the development of autoimmunity following viral infection. 相似文献
7.
K N Priftis A Papadimitriou E Gatsopoulou P K Yiallouros A Fretzayas P Nicolaidou 《The European respiratory journal》2006,27(2):316-320
The present authors evaluated adrenal reserve in asthmatic children on long-term inhaled corticosteroids and whether possible adrenal suppression could be predicted by growth retardation. Low-dose synacthen test (0.5 microg x 1.73 m(-2)) was performed in 72 asthmatic children with a median age of 9.4 (range 4.2-15.7) yrs on long-term treatment (median 18 (range 6-84) months) with low-to-moderate doses (median 363 (range 127-1012) microg x m(-2)) of inhaled budesonide, as well as in 30 controls. Adrenal suppression was considered as a peak serum cortisol <495 nmol x L(-1). The current authors calculated height standard deviation score (HSDS) at the time of testing and height velocity SDS (HVSDS) in the preceding year. Mean HSDS was 0.06+/-1.3 and HVSDS was -0.9+/-2.3. Adrenal suppression was disclosed in 15 asthmatic children (20.8%). There were no differences in HSDS and HVSDS between children with and without adrenal suppression. There was no correlation between peak cortisol response and dose or duration of treatment. However, a positive relationship between HVSDS and duration of treatment was noted. These data suggest that long-term treatment of asthmatic children with low and moderate doses of inhaled budesonide may result in mild adrenal suppression that cannot be predicted by growth deceleration. The negative influence of inhaled corticosteroids on growth becomes less the longer the duration of treatment. 相似文献
8.
G A Pitoulias M D Tachtsi P Z Tsiaousis D K Papadimitriou 《International angiology》2007,26(3):270-278
AIM: The majority of patients with carotid occlusive disease (COD) have one or more of the conventional risk factors of atherosclerosis. In addition, hyperhomocysteinemia (HHCY) and hypercoagulable state (HCGS) are increasingly recognized as potentially 'novel' risk factors. The aim of this study was to determine the role of these factors in carotid plaque evolution and clinical manifestation of COD. METHODS: Between September 2003 and 2005, 153 patients were admitted in our Department with clinical and duplex ultrasound evidence of severe (>70%) COD as operative candidates and 33 patients with evidence of moderate (50-69%) stenosis included in the protocol of conservative treatment and lifelong observation. Conventional risk factors of atherosclerotic disease and plasma levels of homocysteine (HCY), fibrinogen (FBG), protein C (PC), protein S, antithrombin III and activated protein C resistance were recorded in all patients. The degree of carotid stenosis was measured in a carotid angiogram following North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria for all operative candidates. Angiographic workup revealed 147 carotid stenoses >70% and 16 internal carotid occlusions in 82 symptomatic and 52 asymptomatic patients, while in 19 patients the carotid stenosis was moderate (50-69%) and these patients included in the conservative treatment group. The study of the 'novel' and conventional risk factors was performed with univariate and multivariate statistical analysis as well as with correlational analysis of HCY and the other risk factors between patients with severe or moderate COD and between symptomatic and asymptomatic patients with carotid stenosis >70%. RESULTS: Our data showed that HHCY was a strong independent risk factor of symptomatic carotid disease >70%. In addition, the coexistence of high FBG levels and thrombophilia factor deficiency with HHCY was significantly related with the clinical manifestation of COD. CONCLUSION: HHCY and HCGS are often detected among patients with severe and symptomatic carotid stenosis. The early diagnosis and treatment of these deficiencies might be helpful for the management of COD, but their role in future clinical practice is yet to be determined. 相似文献
9.
G. Xiromerisiou G. M. Hadjigeorgiou V. Gourbali J. Johnson I. Papakonstantinou A. Papadimitriou A. B. Singleton 《European journal of neurology》2007,14(1):7-11
Mutations in SNCA and LRRK2 genes, encoding alpha-synuclein and leucine-rich repeat kinase 2, respectively, cause autosomal dominant Parkinson's disease (AdPD). The LRRK2 G2019S (c.6055G > A) and R1441G (c.4321C > G) mutations have also been identified in sporadic PD (sPD). We studied 55 unrelated patients with AdPD, 235 patients with sPD, and 235 healthy age- and gender-matched controls all of Greek origin. Patients with AdPD were screened for SNCA and LRRK2 mutations by direct sequencing. SNCA gene dosage analysis was also performed for AdPD using quantitative duplex polymerase chain reaction of genomic DNA. In addition, we investigated the frequency of the LRRK2 G2019S mutation in sPD. We found no missense mutations or multiplications in the SNCA gene. Here we report two novel variants, A211V (c.632C > T) and K544E (c.1630A > G) in LRRK2 gene in two patients with AdPD that was not present in controls. We identified only one patient with sPD (1/235; 0.4%) carrying the G2019S mutation. LRRK2 mutations are present in AdPD and sPD patients of Greek origin. 相似文献
10.
Milingos S Protopapas A Papadimitriou C Rodolakis A Kallipolitis G Skartados N Markaki S Dimopoulos MA Antsaklis A 《Journal of minimally invasive gynecology》2007,14(1):43-48
STUDY OBJECTIVE: To assess whether laparoscopy is a reliable technique for the investigation of women presenting with ascites and in whom the diagnosis remains obscure. DESIGN: Prospective nonrandomized clinical study (Canadian Task Force classification II-2). SETTING: University Departments of a tertiary referral center. PATIENTS: Women presenting in our institution with ascites in whom the diagnosis remained obscure after an extensive nonoperative diagnostic work-up. INTERVENTION: Undiagnosed cases were submitted to laparoscopy, and selective biopsy specimens were taken for histologic study. MEASUREMENTS AND MAIN RESULTS: Over a 3-year period, 73 patients were admitted to our institution with diffuse ascites. In 9 patients (12.3%), the diagnosis remained obscure, and these patients were further investigated with laparoscopy. Selective biopsy specimens obtained at laparoscopy clarified the specific cause of the ascites in all 9 patients. Peritoneal carcinomatosis was responsible in 5 patients (a metastatic gastrointestinal tumor in 1 patient, a malignant mesothelioma of the peritoneum in 1 patient, and a serous papillary carcinoma of the peritoneum and of the ovary in 2 and 1 patients, respectively). Three patients were found with miliary peritoneal tuberculosis, and the last patient had an unusual peritoneal reaction to methylene blue after laparoscopic adhesiolysis. CONCLUSION: Laparoscopy is a valuable means of assessing the peritoneal cavity in patients with unexplained ascites, where the primary cause remains unclear. The diagnosis can be accurately made with selective biopsy specimens, and appropriate treatment can be instituted without delay. 相似文献