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In the context of a medical surveillance program aimed at preventing cancer risk from exposure to ionizing radiation, we investigated chromosomal damage in peripheral lymphocytes from 37 hospital workers exposed to low levels of ionizing radiation and 37 controls. The micronuleus (MN) assay was used as a biomarker of genetic damage. The influence of confounding factors like smoking status, age and gender was investigated by multiple regression analysis. The results indicated that, overall, MN frequency was higher in exposed workers than in controls, although the difference was not statistically significant. Interestingly, smoking status significantly raised MN frequency among the exposed workers but not among controls. This suggests that smoking can influence chromosomal damage induced in humans by ionizing radiation. Among both exposed workers and controls, MN frequency was found to increase with age. Female gender influenced the increase in MN frequency in the exposed group. Our results suggest that the effect of cigarette smoking should be carefully factored into genetic monitoring studies assessing the risks associated with low level radiation exposure. 相似文献
3.
Both Human Immunodeficiency Virus Cellular DNA Sequencing and Plasma RNA Sequencing Are Useful for Detection of Drug Resistance Mutations in Blood Samples from Antiretroviral-Drug-Naive Patients 下载免费PDF全文
4.
Saverio Cinti Massimo Cigolini Manrico Morroni M. Cristina Zingaretti 《Anatomical record (Hoboken, N.J. : 2007)》1989,224(4):466-472
Differentiation of adipocytes from their precursor cells (preadipocytes) is an important problem in the study of the pathogenesis of obesity. Unfortunately, among the immature stages of adipocytes, only relatively differentiated forms can be identified by their fine structure; because early preadipocytes cannot be distinguished from fibroblasts solely on the basis of their morphology, it is impossible to assess the size of the preadipocyte population. S-100 protein has been identified in various mammalian tissues and recently mature adipocytes have been shown to be positive for this protein. Because fibroblasts are negative for S-100 protein, the present study tested the S-100 immunoreactivity of preadipocytes by the peroxidase-antiperoxidase (PAP) preembedding method at the ultrastructural level both in vivo and in culture. Mature adipocytes and early preadipocytes, including fibroblast-like cells devoid of lipid droplets, were positive both in vivo and in culture. Endothelial cells and pericytes were negative; but flattened, lipid-free, fibroblast-like cells surrounding the pericytes were positive. True fibroblasts both in vivo and in culture were negative. Therefore, S-100 protein can be a useful biochemical marker in distinguishing fibroblasts from early preadipocytes. 相似文献
5.
Leonard A. Herzenberg Charles Hsu Saverio Alberti Paula Kavathas 《Medical oncology (Northwood, London, England)》1984,1(4):219-224
In order to facilitate cloning of genes for cell surface molecules, we cotransfected LTK? mouse fibroblasts with thymidine kinase (TK) genes and total human or mouse DNA. TK+ cells, selected by growth in HAT medium, were stained with fluorochrome conjugated monoclonal antibodies or other fluorescent ligands which bind to one or another membrane differentiation antigen or receptor. We isolated fluorescent transfectants expressing these molecules using a fluorescence activated cell sorter (FACS). For some antigens, spontaneous gene amplification occurred. By repeated cycles of FACS sorting and regrowth we obtained high expressing clones. We then isolatedcDNA and genomic clones using selectedcDNA probes to screen phage withcDNA inserts. DNA from virtually any tissue source transfected equally well for the various molecules except for DNA from a trophoblast derived choriocarcinoma cell line which did not transfect for Leu-2. 相似文献
6.
Barbara Colitti Luigi Bertolotti Alessandro Mannelli Gianmarco Ferrara Andrea Vercelli Andrea Grassi Claudio Trentin Saverio Paltrinieri Chiara Nogarol Nicola Decaro Emiliana Brocchi Sergio Rosati 《Emerging infectious diseases》2021,27(7):1919
We conducted a serologic survey among dogs and cats in Italy to detect antibodies against severe acute respiratory syndrome virus 2 (SARS-CoV-2). We found that SARS-CoV-2 seroprevalence was higher among cats (16.2%) than dogs (2.3%). In addition, seroprevalence was higher among animals living in close contact with SARS-CoV-2–positive owners. 相似文献
7.
F. Virdis I. Reccia S. Di Saverio G. Tugnoli S.H. Kwan J. Kumar J. Atzeni M. Podda 《Diagnostic and interventional imaging》2019,100(2):65-75
Purpose
This purpose of this systematic review was to determine the safety and efficacy of arterial embolization as the primary treatment for grade III-V liver trauma, excluding the postoperative use of arterial embolization.Material and methods
A total of 24 studies published between January 2000 and June 2018 qualified for inclusion in this study. Four of them were prospective studies and 20 were retrospective. A total of 3855 patients (mean age, 33.5 years; range: 22–52.5 years) were treated non-operatively and 659 patients (659/3855; 17.09%) with hepatic hemorrhage underwent primary arterial embolization from 2000 to 2017. Indication for arterial embolization was a contrast blush visible on computed tomography in hemodynamically stable patient in all studies.Results
The arterial embolization success rate ranged from 80% to 97%. The most commonly reported complication was bile leak, with an incidence of 5.7%. Nineteen bilomas (2.8%) were reported in five studies with a range between 4% and 45%. Hepatic ischemia was reported in eight studies, with a mean incidence of 8.6%.Conclusion
Primary arterial embolization has a high success rate in patients with hepatic trauma. Complications, including biloma and hepatic ischemia, have acceptable rates in the context of a minimally-invasive procedure that allows stabilization of life-threatening, complex liver injuries. 相似文献8.
Hamdan MH Barbera S Kowal RC Page RL Ramaswamy K Joglar JA Karimkhani V Smith ML 《The American journal of cardiology》2002,89(9):1047-1051
This study assesses the effect of biventricular pacing on sympathetic nerve activity (SNA) in patients with depressed ejection fraction and intraventricular conduction delay (IVCD). Biventricular pacing has been shown to result in hemodynamic improvement in patients with depressed ejection fraction and IVCD. The effect of biventricular pacing on SNA, however, remains unclear. A total of 15 men with a mean ejection fraction of 25 +/- 4% were enrolled. Arterial pressure, central venous pressure and SNA were recorded during 3 minutes of right atrial (RA) pacing and RA-biventricular pacing. Pacing was performed at a rate 5 to 10 beats faster than sinus rhythm, with an atrioventricular interval equal to 100 ms during RA-biventricular pacing. RA-biventricular pacing resulted in greater arterial pressures (p <0.05) than RA pacing (146 +/- 15/83 +/- 11 vs 141 +/- 15/80 +/- 10 mm Hg). There were no differences in central venous pressures between the 2 pacing modes (p = 0.76). SNA was significantly less during RA-biventricular pacing (727 +/- 242 U) than during RA pacing (833 +/- 332 U) (p <0.02). Furthermore, there was a positive correlation between baseline QRS duration and the decrease in SNA noted with RA-biventricular pacing (r = 0.58, p = 0.03). Biventricular pacing results in improved hemodynamics and a decrease in SNA compared with intrinsic conduction in patients with left ventricular dysfunction and IVCD. If the current findings are also present with chronic biventricular pacing, then this form of therapy may have a positive impact on mortality. 相似文献
9.
Harry Gibbs Ben Freedman Mårten Rosenqvist Saverio Virdone Wael Al Mahmeed Giuseppe Ambrosio A. John Camm Barry Jacobson Carlos Jerjes-Sanchez Gloria Kayani Ali Oto Elizaveta Panchenko Hany Ragy Ajay K. Kakkar 《The American journal of medicine》2021,134(7):893-901.e11
BackgroundAsymptomatic atrial fibrillation is often detected incidentally. Prognosis and optimal therapy for asymptomatic compared with symptomatic atrial fibrillation is uncertain. This study compares clinical characteristics, treatment, and 2-year outcomes of asymptomatic and symptomatic atrial fibrillation presentations.MethodsGlobal Anticoagulant Registry in the Field-Atrial Fibrillation (GARFIELD-AF) is a global, prospective, observational study of newly diagnosed atrial fibrillation with ≥1 stroke risk factors (http://www.clinicaltrials.gov, unique identifier: NCT01090362). Patients were characterized by atrial fibrillation-related symptoms at presentation and the CHA2DS2-VASc score. Two-year follow-up recorded anticoagulation patterns (vitamin K antagonist, direct oral anticoagulants, parenteral therapy) and outcomes (stroke/systemic embolism, all-cause mortality, and bleeding).ResultsAt presentation, of 52,032 eligible patients, 25.4% were asymptomatic and 74.6% symptomatic. Asymptomatic patients were slightly older (72 vs 70 years), more often male (64.2% vs 52.9%), and more frequently initiated on anticoagulation ± antiplatelets (69.4% vs 66.0%). No difference in events (adjusted hazard ratios, 95% confidence interval) for nonhemorrhagic stroke/systemic embolism (1.19, 0.97-1.45), all-cause mortality (1.06, 0.94-1.20), or bleeding (1.02, 0.87-1.19) was observed. Anticoagulation was associated with comparable reduction in nonhemorrhagic stroke/systemic embolism (0.59, 0.43–0.82 vs 0.78, 0.65–0.93) and all-cause mortality (0.69, 0.59-0.81 vs 0.77, 0.71-0.85) in asymptomatic versus symptomatic, respectively.ConclusionsMajor outcomes do not differ between asymptomatic and symptomatic atrial fibrillation presentations and are comparably reduced by anticoagulation. Opportunistic screening-detected asymptomatic atrial fibrillation likely has the same prognosis as asymptomatic atrial fibrillation at presentation and likely responds similarly to anticoagulation thromboprophylaxis. 相似文献
10.
Gregoric ID Cohn WE Akay MH La Francesca S Myers T Frazier OH 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2008,35(2):184-185
The CentriMag left ventricular assist system can be used for perioperative or postcardiotomy circulatory support of the failing heart. The device resides at the patient's bedside, and the cannulae are usually inserted through a midline sternotomy, with the inflow cannula in the left ventricle or right superior pulmonary vein and the outflow cannula in the aorta. In a patient whose chest has been closed and who has a delayed need for temporary mechanical support, a less invasive method of left ventricular assist device cannula insertion is preferred. In these cases, the CentriMag cannulae can be inserted through a right minithoracotomy with the inflow cannula in the right superior pulmonary vein and the outflow cannula in the aorta, with no heparinization. Herein, we describe this approach in a patient who experienced postcardiotomy cardiogenic shock after aortocoronary bypass surgery. This technique may facilitate ambulation and recovery in selected patients. 相似文献