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71.
Daria Prokhorova Natalya Zhukova Anna Lemza Mariia Sergeeva Rinat Amirkhanov Grigory Stepanov 《Viruses》2022,14(2)
Influenza A virus (IAV) causes a respiratory infection that affects millions of people of different age groups and can lead to acute respiratory distress syndrome. Currently, host genes, receptors, and other cellular components critical for IAV replication are actively studied. One of the most convenient and accessible genome-editing tools to facilitate these studies is the CRISPR/Cas9 system. This tool allows for regulating the expression of both viral and host cell genes to enhance or impair viral entry and replication. This review considers the effect of the genome editing system on specific target genes in cells (human and chicken) in terms of subsequent changes in the influenza virus life cycle and the efficiency of virus particle production. 相似文献
72.
Lombardi CP Raffaelli M D'alatri L De Crea C Marchese MR Maccora D Paludetti G Bellantone R 《World journal of surgery》2008,32(5):693-700
Background Voice and swallowing symptoms are frequently reported after thyroidectomy even in absence of objective voice alterations.
We evaluated the influence of the video-assisted approach on voice and swallowing outcome of thyroidectomy.
Methods Sixty-five patients undergoing total thyroidectomy (TT) were recruited. Eligibility criteria were: nodule size ≤30 mm, thyroid
volume ≤30 ml, no previous neck surgery. Exclusion criteria were: younger than aged 18 years and older than aged 75 years,
vocal fold paralysis, history of voice, laryngeal or pulmonary diseases, malignancy other than papillary thyroid carcinoma.
Patients were randomized for video-assisted (VAT) or conventional (CT) thyroidectomy. Videostrobolaryngoscopy (VSL), acoustic
voice analysis (AVA), and maximum phonation time (MPT) evaluation were performed preoperatively and 3 months after TT. Subjective
evaluation of voice (voice impairment score = VIS) and swallowing (swallowing impairment score = SIS) were obtained preoperatively,
1 week, 1 month, and 3 months after TT.
Results Fifty-three patients completed the postoperative evaluation: 29 in the VAT group, and 24 in the CT group. No laryngeal nerves
injury was shown at postoperative VSL. Mean postoperative MPT, F
0, F
low, F
high, and the number of semitones were significantly reduced in the CT group but not in the VAT group. Mean VIS 3 months after
surgery was significantly higher than preoperatively in CT group but not in the VAT group. Mean SIS was significantly decreased
1 and 3 months after VAT but not after CT.
Conclusions The incidence and the severity of early voice and swallowing postthyroidectomy symptoms are significantly reduced in patients
who undergo VAT compared with conventional surgery.
Presented at the ISW2007—IAES free paper session, Montreal, Canada, August 26–30, 2007. 相似文献
73.
Nick Gravish Daria Monaenkova Michael A. D. Goodisman Daniel I. Goldman 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(24):9746-9751
Locomotion emerges from effective interactions of an individual with its environment. Principles of biological terrestrial locomotion have been discovered on unconfined vertical and horizontal substrates. However, a diversity of organisms construct, inhabit, and move within confined spaces. Such animals are faced with locomotor challenges including limited limb range of motion, crowding, and visual sensory deprivation. Little is known about how these organisms accomplish their locomotor tasks, and such environments challenge human-made devices. To gain insight into how animals move within confined spaces, we study the locomotion of the fire ant Solenopsis invicta, which constructs subterranean tunnel networks (nests). Laboratory experiments reveal that ants construct tunnels with diameter, D, comparable to body length, L = 3.5 ± 0.5 mm. Ants can move rapidly (> 9 bodylengths per s) within these environments; their tunnels allow for effective limb, body, and antennae interaction with walls, which facilitate rapid slip-recovery during ascending and descending climbs. To examine the limits of slip-recovery in artificial tunnels, we perform perturbations consisting of rapid downward accelerations of the tunnels, which induce falls. Below a critical tunnel diameter, Ds = 1.31 ± 0.02 L, falls are always arrested through rapid interaction of appendages and antennae with tunnel walls to jam the falls. Ds is comparable to the size of incipient nest tunnels (D = 1.06 ± 0.23 L), supporting our hypothesis that fire ants construct environments that simplify their control task when moving through the nest, likely without need for rapid nervous system intervention. 相似文献
74.
Gelena V. Lifshitz Dmitry D. Zhdanov Anastasia V. Lokhonina Daria D. Eliseeva Elena Y. Lyssuck Igor A. Zavalishin 《Autoimmunity》2016,49(6):388-396
Multiple sclerosis (MS) is an autoimmune disease characterized by defect in regulatory function of CD4+CD25+ T cells. We demonstrated difference in proportion of regulatory T cells CD4+CD25+FoxP3+CD127low (Tregs) within the same patients’ relapse and remission. Proportion of peripheral Tregs (pTregs) dropped almost two times in the relapse compare to remission. Levels of pTregs in patients’ remission were lower than in healthy donors. Suppressive ability of pTregs was decreased in MS patients compared to healthy donors. Injections of expanded ex vivo autologous Tregs (eTregs) could be helpful in bringing up the level of Tregs in patients’ blood. We developed a simple method for ex vivo expansion of autologous Tregs within a short period of time. The final pool of cells consisted of 90-95% eTregs. When we started the culture with 10-20?×?106 CD4+ T cells, we yield 300-400?×?106 eTregs in a week. Expression of FoxP3 and Helios was calculated by two methods. Expanded ex vivo patients’ and donors’ Tregs were characterized by increased from three to five times expression of FoxP3, as well as almost doubled Helios expression. Peripheral Tregs in MS patients have decreased demethylation of FoxP3 gene promoter in comparison with donors. On the contrary, eTregs showed stable up-regulated demethylation without difference between MS patients and donors. MS patients’ and donors’ eTregs have much more suppressive ability than pTregs. Our data showed that eTregs can be applied as immunotherapy for MS patients and other autoimmune diseases if further investigated. 相似文献
75.
76.
Background
Aim: To estimate the impact of smoking restrictions in homes and schools, and tobacco advertising and information on smoking initiation by young people in Ukraine. 相似文献77.
Pharmacokinetics and electrocardiographic pharmacodynamics of artemether-lumefantrine (Riamet) with concomitant administration of ketoconazole in healthy subjects
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Lefèvre G Carpenter P Souppart C Schmidli H McClean M Stypinski D 《British journal of clinical pharmacology》2002,54(5):485-492
AIMS: To evaluate whether the potent CYP3A4 inhibitor ketoconazole has any influence on the pharmacokinetic and electrocardiographic parameters of the antimalarial co-artemether (artemether-lumefantrine) in healthy subjects. METHODS: Sixteen subjects were randomized in an open-label, two period crossover design study. Subjects received a single dose of co-artemether (day 1) either alone or in combination with multiple oral doses of ketoconazole (400 mg on day 1 followed by 200 mg o.d. for 4 additional days). Serial blood samples were taken and assayed for artemether and its main active metabolite dihydroartemisinin (DHA), and lumefantrine. RESULTS: The pharmacokinetics of artemether, its metabolite DHA, and lumefantrine were influenced by the presence of ketoconazole. AUC(0, infinity ) was increased from 320 to 740 ng ml-1 h (ratio 2.4, 90% CI 2.00, 2.86) for artemether, from 331 to 501 ng ml-1 h (ratio 1.7, 90% CI 1.40, 1.98) for DHA, and from 207 to 333 micro g ml-1 h (ratio 1.7, 90% CI 1.23, 2.21) for lumefantrine in the presence of ketoconazole. Cmax also increased in similar proportions for the three compounds (ratio 2.2 (90% CI 1.78, 2.83), 1.4 (90% CI 1.12, 1.74), and 1.3 (90% CI 0.96, 1.64), respectively). The terminal elimination half-life was increased for artemether (2.5 vs 1.9 h, 90% CI 1.12, 1.72) and DHA (3.1 vs 2.1 h, 90% CI 0.02, 3.36), but remained unchanged for lumefantrine (88 vs 95 h, 90% CI 0.81, 1.04). These increases in exposure to the antimalarial combination were much smaller than observed with food intake (up to 16 fold), and were not associated with increased side-effects or changes in electrocardiographic parameters. The study medications were well tolerated. CONCLUSIONS: The concurrent administration of ketoconazole with co-artemether led to modest increases in artemether, DHA, and lumefantrine exposure in healthy subjects. Dose adjustment of co-artemether is probably unnecessary in falciparum malaria patients when administered in association with ketoconazole or other potent CYP3A4 inhibitors. 相似文献
78.
B7-H1 is up-regulated in HIV infection and is a novel surrogate marker of disease progression 总被引:17,自引:2,他引:15
Trabattoni D Saresella M Biasin M Boasso A Piacentini L Ferrante P Dong H Maserati R Shearer GM Chen L Clerici M 《Blood》2003,101(7):2514-2520
The ligation of programmed death-ligand 1 (B7-H1) to T cells results in the preferential production of interleukin 10 (IL-10). We investigated if B7-H1 would be up-regulated in HIV infection, a disease characterized by increased IL-10 production, by measuring B7-H1, B7-1 (CD80), and B7-2 (CD86) expression and mRNA in 36 HIV-infected patients and in 22 healthy controls (HCs). Results showed that (1) B7-H1 expression and mRNA are augmented in cells of HIV patients; (2) increased IL-10 production in these patients is largely induced by B7-H1-expressing CD14(+) cells; (3) an inverse correlation is detected between B7-H1 expression and CD4 counts, whereas the up-regulation of B7-H1 is directly associated with HIV plasma viremia; (4) antiviral therapy results in the parallel down modulation of IL-10 production and B7-H1 expression/synthesis; and (5) B7-H1/CD80 and B7-H1/CD86 mRNA ratios are increased in peripheral blood mononuclear cells (PBMCs) of HIV patients compared with HCs. B7-H1 synthesis and expression are up-regulated in HIV infection, and the degree of dysregulation correlates with the severity of disease. Aberrant antigen presentation by antigen-presenting cells (APCs) that exhibit increased B7-H1 expression and IL-10 production in HIV infection could be responsible for T-lymphocyte unresponsiveness and loss of protective immunity. B7-H1 is a surrogate marker potentially involved in AIDS disease progression. 相似文献
79.
80.
Critical appraisal of the clinical and pathologic predictors of survival after resection of large hepatocellular carcinoma 总被引:9,自引:0,他引:9
Pawlik TM Poon RT Abdalla EK Zorzi D Ikai I Curley SA Nagorney DM Belghiti J Ng IO Yamaoka Y Lauwers GY Vauthey JN;International Cooperative Study Group on Hepatocellular Carcinoma 《Archives of surgery (Chicago, Ill. : 1960)》2005,140(5):450-7; discussion 457-8
HYPOTHESIS: A subset of patients with hepatocellular carcinoma (HCC) with a diameter of 10 cm or larger may benefit from hepatic resection. DESIGN: Retrospective study of a multi-institutional database. SETTING: Five major hepatobiliary centers. PATIENTS: We identified 300 patients who underwent hepatic resection for HCC 10 cm or larger. MAIN OUTCOME MEASURES: Clinical and pathologic data were collected, and prognostic factors were evaluated by univariate and multivariate analyses. Patient survival was stratified according to a clinical scoring system and pathologic T classification. RESULTS: The perioperative mortality rate was 5%. At a median follow-up of 32 months, the median survival was 20.3 months, and the 5-year actuarial survival rate was 27%. Four clinical factors-alpha-fetoprotein of 1000 ng/mL or higher, multiple tumor nodules, the presence of major vascular invasion, and the presence of severe fibrosis-were significant predictors of poor survival (all P<.05). Patients were assigned a clinical score according to the following risk factors: 1, no factor; 2, one or two factors; or 3, three or four factors. On the basis of the clinical score, patients could be stratified into only 2 distinct prognostic groups: no factor (score of 1) vs 1 or more factors (score of 2 or 3) (P<.001). In contrast, when patients were stratified according to pathologic T classification, 3 distinct groups were identified: T1 vs T2 vs T3 and T4 combined (P<.001). Fifty-six percent of the patients with a clinical score of 2 and 20% of patients with a clinical score of 3 actually had T1 or T2 disease on pathologic examination. CONCLUSIONS: Patients with large HCCs should be considered for liver resection as this treatment is associated with a 5-year survival rate exceeding 25%. Clinical predictors should not be used to exclude patients from surgical resection because these factors do not reliably predict outcome. 相似文献