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81.
Flora Qarri Pranvera Lazo Trajce Stafilov Lirim Bekteshi Katerina Baceva Jani Marka 《Air quality, atmosphere, & health》2014,7(3):297-307
The atmospheric deposition of Al, Cr, Fe, Ni, V, and Zn in Albania was investigated by using carpet-forming moss species (Hypnum cupressiforme) as bioindicators. This research is a part of the international program (International Cooperative Programme (ICP) Vegetation, UNECE) carried out in most European countries since 1987, investigating the impacts of air pollutants on crops and natural vegetation. Sampling was carried out during the dry seasons of autumn 2010 and summer 2011 at 62 sites distributed all over Albania. Unwashed, dried samples were totally digested by using microwave digestion, and the concentrations of metal elements were determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The results reflect local emission points. Only the elements with high values of concentration, Al, Cr, Fe, Ni, V, and Zn, compared to other European countries are discussed in this paper. The median values of chromium (4.75 mg/kg, dry weight (DW)), iron (1,618 mg/kg, DW), nickel (5.85 mg/kg, DW), vanadium (3.51 mg/kg, DW), zinc (13.77 mg/kg, DW), and aluminum (6,974 mg/kg, DW) are similar to those of neighboring countries but higher than those of European countries. An exponentially weighted moving average (EWMA) and univariate control chart was used to investigate the moving range of successive observations and to estimate the variability of the data. Certain local emitters were identified like the iron-chromium metallurgy and cement industry, oil refinery, mining industry, and transport. In addition, natural sources, such as the accumulation of these metals in mosses caused by metal-enriched soils, associated with the wind blowing soils particularly in the southeast direction of the country, were pointed as another local emitting factor. 相似文献
82.
Yulia Lin Everad Tilokee Sophie Charg Asim Alam Christine Cserti‐Gazdewich Wendy Lau Christie Lee Lani Lieberman Paula Nixon Wendy Owens Katerina Pavenski Jacob Pendergrast Elianna Saidenberg Nadine Shehata Robert Skeate Qi‐Long Yi David Conrad Jill Dudebout Cyrus C. Hsia Michael Murphy Oksana Prokopchuk‐Gauk Akshay Shah Ziad Solh Jacqueline Trudeau Michelle P. Zeller Jeannie Callum 《Transfusion》2019,59(6):2141-2149
83.
Podsypanina K Politi K Beverly LJ Varmus HE 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(13):5242-5247
Most, if not all, cancers are composed of cells in which more than one gene has a cancer-promoting mutation. Although recent evidence has shown the benefits of therapies targeting a single mutant protein, little attention has been given to situations in which experimental tumors are induced by multiple cooperating oncogenes. Using combinations of doxycycline-inducible and constitutive Myc and mutant Kras transgenes expressed in mouse mammary glands, we show that tumors induced by the cooperative actions of two oncogenes remain dependent on the activity of a single oncogene. Deinduction of either oncogene individually, or both oncogenes simultaneously, led to partial or complete tumor regression. Prolonged remission followed deinduction of Kras(G12D) in the context of continued Myc expression, deinduction of a MYC transgene with continued expression of mutant Kras produced modest effects on life extension, whereas simultaneous deinduction of both MYC and Kras(G12D) transgenes further improved survival. Disease relapse after deinduction of both oncogenes was associated with reactivation of both oncogenic transgenes in all recurrent tumors, often in conjunction with secondary somatic mutations in the tetracycline transactivator transgene, MMTV-rtTA, rendering gene expression doxycycline-independent. These results demonstrate that tumor viability is maintained by each gene in a combination of oncogenes and that targeted approaches will also benefit from combination therapies. 相似文献
84.
Plasma Levels of Nitrites/Nitrates in Patients with Chronic Atrial Fibrillation are Increased after Electrical Restoration of Sinus Rhythm 总被引:5,自引:0,他引:5
Dragana Nikitovic Evangelos A. Zacharis Emmanuel G. Manios Nikki E. Malliaraki Emmanuel M. Kanoupakis Katerina I. Sfiridaki Emmanuel I. Skalidis Andreas N. Margioris Panos E. Vardas 《Journal of interventional cardiac electrophysiology》2002,7(2):171-176
Introduction: Patients with persistent atrial fibrillation (AF) have hemodynamic changes, which impair endothelial cell function resulting in decreased nitric oxide (NO) production. The aim of this work was to assess endothelial function in AF patients before and at various time points after cardioversion.
Methods: Forty-two patients with AF and 21 normal and age-adjusted healthy controls were studied. Nitrites and nitrates (NO
x
) and von Willebrand factor (vWf) concentrations were measured on blood samples taken just before cardioversion and over a 30 day period after the procedure.
Results: Plasma levels of NO
x
in AF were significantly lower compared to healthy controls (p < 0.001), but after cardioversion gradually increased to approach to those of the healthy controls by the end of the first month of sustained sinus rhythm (p = 0.004). Interestingly plasma levels of NO
x
were negatively correlated to left atrial volume measured by ultrasonography (r = –0.34, p < 0.05). Plasma levels of vWf in AF patients were significantly higher compared to the healthy controls (p < 0.01) but with sustained sinus rhythm decreased (p = 0.02).
Conclusion: The parallel normalization of the NO
x
titers and vWf levels suggests that vascular endothelial function improves after 30 days of normal sinus rhythm. 相似文献
85.
Papavramidis ST Eleftheriadis EE Papavramidis TS Kotzampassi KE Gamvros OG 《Gastrointestinal endoscopy》2004,59(2):296-300
BACKGROUND: Gastrocutaneous fistula is an uncommon and difficult to treat complication that occurs in 0.5% to 3.9% of patients who undergo gastric surgery. Sepsis usually follows, and, when it is not managed effectively, the associated mortality rate can be as high as 85%. A fibrin sealant was used to endoscopically manage gastrocutaneous fistulas that developed in 3 morbidly obese patients after bariatric surgery. METHODS: Two of 14 (14.29%) patients who underwent vertical gastroplasty (MacLean procedure) developed a non-healing gastrocutaneous fistula. In addition, one of 24 (4.17%) patients who had a biliopancreatic diversion with preservation of pylorus developed a gastrocutaneous fistula. Endoscopic application of a fibrin sealant was performed under direct vision via a double-lumen catheter passed through a forward-viewing endoscope. OBSERVATIONS: Treatment was successful in all patients after one or more endoscopic sessions in which the fibrin sealant was applied; no evidence of fistula was found at follow-up endoscopy. CONCLUSIONS: Endoscopic closure of gastrocutaneous fistula with human fibrin tissue sealant is simple, safe, and effective, and, in some cases, can be life-saving. Endoscopic application of fibrin sealant should be considered a therapeutic option for treatment of gastrocutaneous fistula that develops after bariatric surgery. 相似文献
86.
Transjugular intrahepatic portosystemic shunt in cavernomatous portal vein occlusion 总被引:2,自引:0,他引:2
Brountzos EN Malagari K Alexopoulou E Nikolaou VE Panagiotou I Argyriou P Efstathopoulos E Kelekis DA 《Hepato-gastroenterology》2004,51(58):1168-1171
A 72-year-old patient with liver cirrhosis and cavernomatous portal vein occlusion presented with refractory ascites. We treated the patient with transjugular intrahepatic portosystemic shunt: transjugular transhepatic puncture of an intrahepatic hilar collateral vein was performed; transjugular intrahepatic portosystemic shunt was created between the right hepatic vein and the patent superior mesenteric vein using this hilar collateral vein as the connecting pathway. The ascites was resolved and the patient remains asymptomatic, while shunt patency is maintained 16 months after the intervention. 相似文献
87.
Nikolaos Alexopoulos Charalambos Vlachopoulos Konstantinos Aznaouridis Katerina Baou Carmen Vasiliadou Panagiota Pietri Panagiotis Xaplanteris Elli Stefanadi Christodoulos Stefanadis 《European journal of cardiovascular prevention and rehabilitation》2008,15(3):300-305
BACKGROUND: Tea consumption is associated with decreased cardiovascular risk. Flow-mediated dilatation (FMD) of the brachial artery is related to coronary endothelial function and it is an independent predictor of cardiovascular risk. Black tea has a beneficial effect on endothelial function; the effect, however, of green tea on brachial artery reactivity has not been defined yet. DESIGN AND METHODS: We studied 14 healthy individuals (age 30+/-3 years) with no cardiovascular risk factors except from smoking (50%) on three separate occasions on which they took: (a) 6 g of green tea, (b) 125 mg of caffeine (the amount contained in 6 g of tea), or (c) hot water. FMD of the brachial artery was measured before each intervention and 30, 90, and 120 min afterward. High-sensitivity C-reactive protein, interleukins 6 (Il-6) and 1b (Il-1b), total plasma antioxidative capacity, and total plasma oxidative status/stress were measured at baseline and at 120 min after each intervention. RESULTS: Resting and hyperemic brachial artery diameter did not change either with tea or with caffeine. FMD increased significantly with tea (by 3.69%, peak at 30 min, P<0.02), whereas it did not change significantly with caffeine (increase by 1.72%, peak at 30 min, P=NS). Neither tea nor caffeine had any effect on high-sensitivity C-reactive protein, Il-6, Il-1b, total plasma antioxidative capacity, or total plasma oxidative status/stress. CONCLUSION: Green tea consumption has an acute beneficial effect on endothelial function, assessed with FMD of the brachial artery, in healthy individuals. This may be involved in the beneficial effect of tea on cardiovascular risk. 相似文献
88.
Nassis GP Papantakou K Skenderi K Triandafillopoulou M Kavouras SA Yannakoulia M Chrousos GP Sidossis LS 《Metabolism: clinical and experimental》2005,54(11):1472-1479
The aim of this study was to examine the effect of aerobic exercise training on insulin sensitivity in overweight and obese girls. Nineteen overweight and obese girls (mean +/- SD: age, 13.1+/-1.8 years; body mass index, 26.8+/-3.9 kg/m(2)) volunteered for this study. Body composition (dual-energy x-ray absorptiometry), insulin sensitivity (oral glucose tolerance test and homeostasis model assessment estimate of insulin resistance; n=15), adiponectin, C-reactive protein (CRP), interleukin (IL) 6, insulin-like growth factor-1, soluble intercellular adhesion molecule-1 and soluble vascular cell adhesion molecule-1 serum levels, and blood lipids and lipoproteins were assessed before and after 12 weeks of aerobic training. Cardiorespiratory fitness increased by 18.8% (P<.05) as a result of training. The area under the insulin concentration curve (insulin area under the curve) decreased by 23.3% (12781.7+/-7454.2 vs 9799.0+/-4918.6 microU.min/mL before and after intervention, respectively; P=.03). Insulin sensitivity was improved without changes in body weight (pre-intervention, 67.9+/-14.5 kg; post-intervention, 68.3+/-14.0 kg) or percent body fat (pre-intervention, 41.4% +/- 4.8%; post-intervention, 40.7%+/-5.2%). The lower limb fat-free mass increased by 6.2% (P<.01) as a result of training, and changes in lower limb fat-free mass were correlated with changes in the insulin area under the curve (r= -.68; P< .01). Serum adiponectin, IL-6, and CRP concentrations did not change (pre-intervention vs post-intervention: adiponectin, 9.57+/-3.01 vs 9.08+/-2.32 microg/mL; IL-6, 1.67+/-1.29 vs 1.65+/-1.25 pg/mL, CRP, 3.21+/-2.48 vs 2.73+/-1.88 mg/L) whereas insulin-like growth factor-1 was lower after training (pre-intervention, 453.8 +/- 159.3 ng/mL; post-intervention, 403.2+/- 155.1 ng/mL; P<.05). In conclusion, 12 weeks of aerobic training improved insulin sensitivity in overweight and obese girls without change in body weight, percent body fat, and circulating concentrations of adiponectin, IL-6, CRP, and other inflammatory markers. These findings suggest that increased physical activity may ameliorate the metabolic abnormalities associated with obesity in children with a mechanism other than the parameters cited earlier. 相似文献
89.
PFAPA syndrome represents the most common cause of recurrent fever in children in European populations, and it is characterized by recurrent episodes of high fever, pharyngitis, cervical adenitis, and aphthous stomatitis. Many possible causative factors have been explored so far, including infectious agents, immunologic mechanisms and genetic predisposition, but the exact etiology remains unclear. Recent findings demonstrate a dysregulation of different components of innate immunity during PFAPA flares, such as monocytes, neutrophils, complement, and pro-inflammatory cytokines, especially IL-1β, suggesting an inflammasome-mediated innate immune system activation and supporting the hypothesis of an autoinflammatory disease. Moreover, in contrast with previous considerations, the strong familial clustering suggests a potential genetic origin rather than a sporadic disease. In addition, the presence of variants in inflammasome-related genes, mostly in NLRP3 and MEFV, suggests a possible role of inflammasome-composing genes in PFAPA pathogenesis. However, none of these variants seem to be relevant, alone, to its etiology, indicating a high genetic heterogeneity as well as an oligogenic or polygenic genetic background. 相似文献
90.
Liu E Percy MJ Amos CI Guan Y Shete S Stockton DW McMullin MF Polyakova LA Ang SO Pastore YD Jedlickova K Lappin TR Gordeuk V Prchal JT 《Blood》2004,103(5):1937-1940
The first congenital defect of hypoxia-sensing homozygosity for VHL 598C>T mutation was recently identified in Chuvash polycythemia. Subsequently, we found this mutation in 11 unrelated individuals of diverse ethnic backgrounds. To address the question of whether the VHL 598C>T substitution occurred in a single founder or resulted from recurrent mutational events in human evolution, we performed haplotype analysis of 8 polymorphic markers covering 340 kb spanning the VHL gene on 101 subjects bearing the VHL 598C>T mutation, including 72 homozygotes (61 Chuvash and 11 non-Chuvash) and 29 heterozygotes (11 Chuvash and 18 non-Chuvash), and 447 healthy unrelated individuals from Chuvash and other ethnic groups. The differences in allele frequencies for each of the 8 markers between 447 healthy controls (598C) and 101 subjects bearing the 598T allele (P < 10(-7)) showed strong linkage disequilibrium. Haplotype analysis indicated a founder effect. We conclude that the VHL 598C>T mutation, the most common defect of congenital polycythemia yet found, was spread from a single founder 1,000 to 62,000 years ago. 相似文献