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101.
Persistence of a Repressed Epstein-Barr Virus Genome in Burkitt Lymphoma Cells Made Resistant to 5-Bromodeoxyuridine 总被引:5,自引:6,他引:5
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Berge Hampar Jeffery G. Derge Lidia M. Martos John L. Walker 《Proceedings of the National Academy of Sciences of the United States of America》1971,68(12):3185-3189
The P3HR-1 line of human lymphoblastoid cells that is Epstein-Barr virus positive was made resistant to 5-bromodeoxyuridine. Epstein-Barr virus-associated antigens, but not virus particles, were produced in P3HR-1(BU) cells maintained on 5-bromodeoxyuridine. However, virus particles did appear within 4 days after removal of the drug. Thymidine kinase activity was limited to P3HR-1(BU) cells producing viral antigen, whereas all control P3HR-1 cells showed thymidine kinase activity regardless of viral antigen synthesis.Cellular DNA in most P3HR-1(BU) cells was made via pathways that did not involve thymidine kinase. In cells having a pathway that involved thymidine kinase, a second DNA of density 1.71 g/cm(3), corresponding to Epstein-Barr virus, was detected.IT WAS CONCLUDED THAT: (a) a repressed Epstein-Barr virus genome persists in P3HR-1(BU) cells that do not contain thymidine kinase, with activation of the viral genome being accompanied by productive infection and the appearance of enzyme, and (b) thymidine kinase activity in P3HR-1(BU) cells could be used as a marker for viral genome expression. 相似文献
102.
Giuseppe d'Ambrosio Laura del Prete Chiara Grimaldi Arianna Bertocchini Cristina Lo Zupone Lidia Monti Jean de Ville de Goyet 《Journal of pediatric surgery》2014
Purpose
Malignant tumors of the common bile duct or of the pancreas head are uncommon in childhood [Perez EA, Gutierrez JC, Koniaris LG, Neville HL, Thompson WR, Sola JE. Malignant pancreatic tumors: incidence and outcome in 58 pediatric patients. J Pediatr Surg. 2009; Jan; 44 (1): 197–203]. With radical surgery being the standard cure for nonmetastatic diseases, pancreaticoduodenectomy (PD) is the best choice when the tumor is localized in the head of the pancreas, or in the lower portion of the common bile duct. The purpose of the present study is to describe five consecutive children managed by PD, and reviewing the particular aspects and results of this rare procedure in children.Methods
Between 2007 and 2010, five patients (median age: 7 years) underwent PD for nonmetastatic malignant tumors. In two cases, PD was performed en bloc with a right hepatectomy in order to achieve the radical resection of a recurrent biliary sarcoma. Four patients benefited from a “pylorus-preserving” PD procedure. In two patients, resection of the portal vein and vascular reconstruction was performed, and in one case, an extended resection of the biliary ductal system was necessary.Results
All resection margins were clear. The postoperative course was uneventful, with no pancreatic or biliary leakage in all of the patients. Oral refeeding was achieved by the eighth postoperative day. In two cases, a late revision of pancreatic–jejunal anastomosis was performed because of mild steatorrea and a suspected anastomotic stricture. Two of the patients, who were subsequently operated on second hand, for biliary sarcoma, died from the recurrence; while three of the others, with pancreatic malignancies, are alive and well, with a good functional outcome.Conclusions
Surgical resection is the treatment of choice for tumors of the pancreatic head area. In the absence of regional or metastatic extension, the radicality of primary intervention is associated with favorable outcomes. Good functionality results were observed after the PD was limited to the head of the pancreas and subject to pylorus-preserving techniques. 相似文献103.
104.
Agata Kosmaczewska Jerzy Swierkot Lidia Ciszak Aleksandra Szteblich Agnieszka Chrobak Lidia Karabon Anna Partyka Jacek Szechinski Piotr Wiland Irena Frydecka 《Rheumatology international》2014,34(2):243-253
Systemic immune defects might reflect severely dysregulated control of chronic inflammation related to disease progression. Th17/Treg cell imbalance has been demonstrated to be involved in rheumatoid arthritis (RA) pathogenesis. Despite controversial results, a growing anti-inflammatory role in this process has been recently attributed to Th1 responses. The aim of the study was to estimate the extent of Th1/Th17/Treg imbalance in peripheral blood (PB) of patients with short- and long-term RA in relation to cytokine milieu and its reversal after therapy with methotrexate and/or TNF inhibitors, respectively. Patients with different duration of RA (median 6 vs. 120 months) in the active phase of RA were enrolled in this study. We performed flow cytometric analysis of PB Th1, Th17, and Treg populations together with estimation of serum cytokine concentrations using cytometric bead array. Disease activity was calculated on the basis of clinical and biochemical indices of inflammation (DAS28, ESR, CRP). All parameters were measured and correlated with each other before and after 6 months therapy. Elevated levels of circulating Th17 cells and IL-6 were found in all active patients, of which Th17 cells were down-regulated by the treatment. Significantly reduced Th1 and functional CTLA-4+ Treg cell frequencies as well as Th1 cytokines observed only in progressive RA seemed to be irreversible. Although therapy induced clinical improvement in almost all patients, those with advanced RA remained with signs of inflammation. Our report demonstrates that both the extent of systemic immune abnormalities and their restoration are dependent on duration of the active RA. 相似文献
105.
Allan K.N. Alencar Sharlene L. Pereira Flavia E. da Silva Luiza V.P. Mendes Valéria do M.N. Cunha Lidia M. Lima Tadeu L. Montagnoli Celso Caruso-Neves Emanuelle B. Ferraz Roberta Tesch José H.M. Nascimento Carlos M.R. Sant'Anna Carlos A.M. Fraga Eliezer J. Barreiro Roberto T. Sudo Gisele Zapata-Sudo 《International journal of cardiology》2014
Background
Pulmonary arterial hypertension (PAH) is a disease that results in right ventricular (RV) dysfunction. While pulmonary vascular disease is the primary pathological focus, RV hypertrophy and RV dysfunction are the major determinants of prognosis in PAH. The aim of this study was to investigate the effects of (E)-N′-(3,4-dimethoxybenzylidene)-4-methoxybenzohydrazide (LASSBio-1386), an N-acylhydrazone derivative, on the lung vasculature and RV dysfunction induced by experimental PAH.Methods
Male Wistar rats were injected with a single dose (60 mg/kg, i.p.) of monocrotaline (MCT) and given LASSBio-1386 (50 mg/kg, p.o.) or vehicle for 14 days. The hemodynamic, exercise capacity (EC), endothelial nitric oxide synthase (eNOS), adenosine A2A receptor (A2AR), sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA2a), phospholamban (PLB) expression, Ca2 +-ATPase activity and vascular activity of LASSBio-1386 were evaluated.Results and conclusions
The RV systolic pressure was elevated in the PAH model and reduced from 49.6 ± 5.0 mm Hg (MCT group) to 27.2 ± 2.1 mm Hg (MCT + LASSBio-1386 group; P < 0.05). MCT administration also impaired the EC, increased the RV and pulmonary arteriole size, and promoted endothelial dysfunction of the pulmonary artery rings. In the PAH group, the eNOS, A2AR, SERCA2a, and PLB levels were changed compared with the control; in addition, the Ca2 +-ATPase activity was reduced. These alterations were related with MCT-injected rats, and LASSBio-1386 had favorable effects that prevented the development of PAH. LASSBio-1386 is effective at preventing endothelial and RV dysfunction in PAH, a finding that may have important implications for ongoing clinical evaluation of A2AR agonists for the treatment of PAH. 相似文献106.
Michele Baccarani Brian J. Druker Susan Branford Dong-Wook Kim Fabrizio Pane Lidia Mongay Manisha Mone Christine-Elke Ortmann Hagop M. Kantarjian Jerald P. Radich Timothy P. Hughes Jorge E. Cortes François Guilhot 《International journal of hematology》2014,99(5):616-624
The TOPS trial evaluated high- (800 mg/day; n = 319) versus standard-dose (400 mg/day; n = 157) imatinib in patients newly diagnosed with Philadelphia chromosome-positive chronic myeloid leukemia in chronic phase. Patients had a minimum follow-up of 42 months or discontinued early. Major molecular response (MMR) rates were similar between arms at (51.6 vs 50.2 % for 400 and 800 mg/day, respectively; P = 0.77) and by (75.8 vs 79.0 %; P = 0.4807) 42 months. There were no differences in event-free survival (EFS), progression-free survival (PFS), or overall survival (OS) between arms. The estimated rates of PFS on treatment and OS at 42 months were significantly higher in patients with MMR at 6, 12, and 18 months compared with those without MMR. Adverse events were more frequent with high-dose imatinib. Patients with ≤1 treatment interruption (vs >1) and those able to maintain imatinib ≥600 mg/day (vs <600 mg/day) in the first year of treatment had faster and higher response rates, but no improvement in EFS or PFS. Adherence to prescribed dose without interruption may be more important than initiation of therapy with higher doses of imatinib. Achievement of MMR correlated with long-term clinical outcomes. 相似文献
107.
The primary purpose of this study is to investigate the effect of the electrochemical parameters required in the anodic oxidation process on the friction and wear resistance of the obtained nanoporous aluminum oxide films. The wear resistance of the aluminum oxide films and the electrochemically polished Al1050 alloy were tested using a ball-on-disc tribometer having a corundum ball as counterbody in dry conditions. The friction coefficient graphs were recorded during wear tests at a 5 N normal force simulating the application of nanoporous aluminum oxide films in industrial areas requesting moderate wear resistance. The wear tracks formed on the tested surfaces were analyzed ex situ both qualitatively and quantitatively. Higher wear resistance is showed by nanoporous aluminum oxide films as compared with electro polished Al1050 alloy substrate.The primary purpose of this study is to investigate the effect of the electrochemical parameters required in the anodic oxidation process on the friction and wear resistance of the obtained nanoporous aluminum oxide films. 相似文献
108.
109.
110.
Paolo Gritti Luigi Andrea Lanterna Lidia Rotasperti Matteo Filippini Simone Cazzaniga Carlo Brembilla Tatyana Sarnecki Ferdinando Luca Lorini 《Journal of anesthesia》2014,28(5):687-695