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1.
Cell culture-based transdominant genetic techniques provide new methods for discovering peptide/RNA modulators of cellular pathways. We applied this technology to isolate a peptide inhibitor of human rhinovirus. A green fluorescent protein (GFP)-scaffolded library of cDNA fragments was expressed in HeLa cells from a retroviral vector and screened for inhibitors of rhinovirus-mediated cell killing. A DNA clone, I421, increased cell survival in an HRV14 challenge assay from less than 0.5% to greater than 60%. It encodes a 53-amino-acid C-terminal extension of the GFP scaffold. Particular subclones of Hela cells expressing I421 (exemplified by I421dp3) show a delay in virus production and a 50-fold decrease in viral RNA levels at 6-8 h postinfection. HRV2, HRV14, and HRV16 show a dramatic decrease in plaque-forming ability on I421dp3 while Coxsackievirus B3 showed a small reduction. Levels of ICAM-1, the receptor for the main rhinovirus serotype, are not altered in I421dp3. 相似文献
2.
F. Pisano P. Gontero R. Sylvester S. Joniau V. Serretta S. Larré S. Di Stasi B. van Rhijn A. Witjes A. Grotenhuis R. Colombo A. Briganti M. Babjuk V. Soukup P.U. Malmstrom J. Irani N. Malats J. Baniel J. Palou 《Actas urologicas espa?olas》2021,45(6):473-478
Introduction and objectivesThe goals of transurethral resection of a bladder tumor (TUR) are to completely resect the lesions and to make a correct diagnosis in order to adequately stage the patient. It is well known that the presence of detrusor muscle in the specimen is a prerequisite to minimize the risk of under staging.Persistent disease after resection of bladder tumors is not uncommon and is the reason why the European Guidelines recommended a re-TUR for all T1 tumors. It was recently published that when there is muscle in the specimen, re-TUR does not influence progression or cancer specific survival.We present here the patient and tumor factors that may influence the presence of residual disease at re-TUR.Material and methodsIn our retrospective cohort of 2451 primary T1G3 patients initially treated with BCG, pathology results for 934 patients (38.1%) who underwent re-TUR are available. 74% had multifocal tumors, 20% of tumors were more than 3 cm in diameter and 26% had concomitant CIS.In this subgroup of patients who underwent re-TUR, there was no residual disease in 267 patients (29%) and residual disease in 667 patients (71%): Ta in 378 (40%) and T1 in 289 (31%) patients. Age, gender, tumor status (primary/recurrent), previous intravesical therapy, tumor size, tumor multi-focality, presence of concomitant CIS, and muscle in the specimen were analyzed in order to evaluate risk factors of residual disease at re-TUR, both in univariate analyses and multivariate logistic regressions.ResultsThe following were not risk factors for residual disease: age, gender, tumor status and previous intravesical chemotherapy. The following were univariate risk factors for presence of residual disease: no muscle in TUR, multiple tumors, tumors > 3 cm, and presence of concomitant CIS. Due to the correlation between tumor multi-focality and tumor size, the multivariate model retained either the number of tumors or the tumor diameter (but not both), p < 0.001. The presence of muscle in the specimen was no longer significant, while the presence of CIS only remained significant in the model with tumor size, p < 0.001.ConclusionsThe most significant factors for a higher risk of residual disease at re-TUR in T1G3 patients are multifocal tumors and tumors more than 3 cm. Patients with concomitant CIS and those without muscle in the specimen also have a higher risk of residual disease. 相似文献
3.
Huschtscha L Bartier W Malmstrom A Tattersall M 《International journal of oncology》1995,6(3):585-593
The mechanism of cell death, apoptosis or necrosis, was determined morphologically and by DNA gel electrophoresis in 3 human leukaemic T-cell lines (CCRF-CEM.f2, CCRF-HSB and MOLT.4) after treatment with cytotoxic drugs. These include one hormone, dexamethasone (DXM); the DNA damaging agents, melphalan, cisplatin, bleomycin, mitomycin C and mithramycin; inhibitors of DNA synthesis, aphidicolin, cytosine arabinoside (Ara-C), methotrexate (MTX), 5-fluoro-2'-deoxyuridine (FUdR) and 5-fluorouracil (5-FU); and other metabolic inhibitors, bromo-2'-deoxy-2'-uridine (BUdR), actinomycin D, 5-azacytidine (5-AC), cycloheximide, vincristine, etoposide and adriamycin. When cell death was assessed morphologically apoptotic cell death was apparent in the three cell lines 48 hours after all drug treatments. However, a distinct pattern of DNA breakdown was observed for each cell line. A smear of DNA on agarose gels was seen for CCRF-CEM.f2 with 5-FU and mithramycin treatments whilst CCRF-HSB cells showed a similar DNA profile after 5-FU and MTX treatments. All drug treatments of MOLT.4 cells produced a necrotic pattern of DNA degradation. Cycloheximide, an inhibitor of protein synthesis reduced DNA fragmentation of CCRF-CEM.f2 cells treated with DXM, MTX and FUdR indicating that protein synthesis is required for cytotoxicity by apoptosis. However, the extent of DNA fragmentation caused by 5-FU was not significantly affected by cycloheximide. These results indicate that at least morphological and electrophoretic criteria should be used to avoid differing conclusions about modes of cell death. 相似文献
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6.
Montelukast added to inhaled beclomethasone in treatment of asthma. Montelukast/Beclomethasone Additivity Group 总被引:11,自引:0,他引:11
Laviolette M Malmstrom K Lu S Chervinsky P Pujet JC Peszek I Zhang J Reiss TF 《American journal of respiratory and critical care medicine》1999,160(6):1862-1868
The primary objective of this study was to determine whether montelukast, an oral leukotriene receptor antagonist, provides additional clinical benefit to the effect of inhaled corticosteroids. A total of 642 patients with chronic asthma (FEV(1) 50 to 85% of predicted value and at least a predefined level of asthma symptoms) incompletely controlled with inhaled beclomethasone, 200 microg twice daily using a spacer device, during the 4-wk run-in period were randomly allocated, in a double-blind, double-dummy manner to one of four treatment groups: (1) montelukast 10 mg plus continuing inhaled beclomethasone; (2) placebo tablet plus continuing inhaled beclomethasone; (3) montelukast 10 mg and inhaled placebo (after blind beclomethasone removal); and (4) placebo tablet and inhaled placebo (after blind beclomethasone removal). The primary endpoints were FEV(1) and daytime asthma symptoms score. Montelukast provided significant (p < 0.05) clinical benefit in addition to inhaled beclomethasone by improving FEV(1), daytime asthma symptom scores, and nocturnal awakenings. Blind removal of beclomethasone in the presence of placebo tablets caused worsening of asthma control, demonstrating that patients received clinical benefit from inhaled corticosteroids. Blind removal of beclomethasone in the presence of montelukast resulted in less asthma control but not to the level of the placebo group. All treatments were well tolerated; clinical and laboratory adverse experiences were generally similar to placebo treatment in this study. In conclusion, montelukast provided additional asthma control to patients benefitting from, but incompletely controlled on, inhaled beclomethasone. 相似文献
7.
Ben P. Werling Timothy L. Dickson Rufus Isaacs Hannah Gaines Claudio Gratton Katherine L. Gross Heidi Liere Carolyn M. Malmstrom Timothy D. Meehan Leilei Ruan Bruce A. Robertson G. Philip Robertson Thomas M. Schmidt Abbie C. Schrotenboer Tracy K. Teal Julianna K. Wilson Douglas A. Landis 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(4):1652-1657
Agriculture is being challenged to provide food, and increasingly fuel, for an expanding global population. Producing bioenergy crops on marginal lands—farmland suboptimal for food crops—could help meet energy goals while minimizing competition with food production. However, the ecological costs and benefits of growing bioenergy feedstocks—primarily annual grain crops—on marginal lands have been questioned. Here we show that perennial bioenergy crops provide an alternative to annual grains that increases biodiversity of multiple taxa and sustain a variety of ecosystem functions, promoting the creation of multifunctional agricultural landscapes. We found that switchgrass and prairie plantings harbored significantly greater plant, methanotrophic bacteria, arthropod, and bird diversity than maize. Although biomass production was greater in maize, all other ecosystem services, including methane consumption, pest suppression, pollination, and conservation of grassland birds, were higher in perennial grasslands. Moreover, we found that the linkage between biodiversity and ecosystem services is dependent not only on the choice of bioenergy crop but also on its location relative to other habitats, with local landscape context as important as crop choice in determining provision of some services. Our study suggests that bioenergy policy that supports coordinated land use can diversify agricultural landscapes and sustain multiple critical ecosystem services.In agricultural landscapes, balancing the provisioning of food and energy with maintenance of biodiversity and ecosystem functions is a global challenge. To avoid impacts on food production, attention is increasingly being focused on the potential for marginal lands to support bioenergy production (1). Marginal lands, those suboptimal for food production, may consist of relatively small areas within generally productive landscapes or larger regions where conditions generally limit crop productivity. However, there is increasing recognition that these lands are already performing a variety of useful functions, and their conversion to bioenergy cropping could reduce these services. For example, in the north central United States, rising commodity prices are predicted to bring marginal croplands—including Conservation Reserve Program lands—into annual crop production with negative impacts on wildlife habitat and water quality (2, 3). With 2013 corn plantings at recent record highs (4) and new reports of grassland and wetland conversion to cropland (5, 6), this may be occurring already.An alternative to annual cropping is conversion of marginal croplands to perennial, cellulosic crops for bioenergy. Although current US biofuel production centers on grain ethanol derived from annual monocultures of maize (Zea mays), this situation could change with full implementation of the 2007 US Energy Independence and Security Act (7), which calls for increased production of cellulosic biofuels. In the Midwest United States, perennial grasses and forbs grown on marginal lands could provide up to 25% of national targets for cellulosic biofuel, with substantial greenhouse gas (GHG) benefits (8). Moreover, increasing the area of perennial cover on the landscape is predicted to positively affect a diverse array of organisms and ecological functions (9–11), leading to important synergies that have not yet informed the ongoing bioenergy debate. Here we provide the most comprehensive empirical evaluation of this hypothesis to date, reporting data that elucidate the impacts of different bioenergy cropping systems on a wide variety of organisms and the ecosystem functions they perform.Previous studies have examined the ability of select bioenergy crops to support specific taxa (12) or individual services such as energy production (13) or GHG mitigation (14), without consideration of the tradeoffs or synergies that can arise when considering entire suites of organisms and ecosystem functions. We report on a unique multidisciplinary study of matched sets of organisms and ecosystem services and show that perennial grass energy crops (switchgrass, Panicum virgatum, and mixed prairie plantings) synergistically enhance diversity of a variety of organisms and levels of the services they provide. We further quantify the importance of landscape context on service provisioning, suggesting that policy supporting intentional design of bioenergy landscapes could increase sustainability of both food and energy production. 相似文献
8.
BACKGROUND: Changes in androgen levels and associations with chronic disease, physical and neuropsychological function and disability in women over the middle to later years of life are not well understood and have not been extensively studied in African American women. AIMS: The present cross-sectional analysis reports such levels and associations in community dwelling, African American women aged 49-65 years from St. Louis, Missouri. METHODS: A home-based physical examination and a health status questionnaire were administered to randomly sampled women. Body composition (DEXA), lower limb and hand-grip muscle strength, physical and neuropsychological function and disability levels were assessed. Blood was drawn and assayed for total testosterone (T), sex hormone-binding globulin (SHBG), dehydroepiandrosterone-sulfate (DHEAS), oestradiol (E2), adiponectin, leptin, triglycerides, glucose, C-reactive protein (CRP) and cytokine receptors (sIL2r, sIL6r, sTNFr1 and sTNFr2). Multiple linear regression modelling was used to identify the best predictors of testosterone, DHEAS and free androgen index (T/SHBG). RESULTS: Seventy-four percent of women were menopausal and a quarter of these were taking oestrogen therapy. DHEAS and E2 declined between the ages of 49 and 65 years, whereas total T, SHBG and FAI remained stable. Total T and DHEAS levels were strongly correlated. In this population sample there were no independent associations of either total T or FAI with indicators of functional limitations, disability or clinically relevant depressive symptoms. Unlike total T and FAI, lower DHEAS levels were independently associated with both higher IADL scores (indicating a higher degree of physical disability) and higher CESD scores (indicating a higher degree of clinically relevant depressive symptoms). CONCLUSION: There is an age-related decline in serum DHEAS in African American women. Lower DHEAS levels appear to be associated with a higher degree of physical disability and depressive symptoms in this population. 相似文献
9.
John E. Rouck T. K. Malmstrom J. E. Morley 《The journal of nutrition, health & aging》2018,22(8):880-884