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51.
Leonardo Furi Maria Laura Ciusa Daniel Knight Valeria Di Lorenzo Nadia Tocci Daniela Cirasola Lluis Aragones Joana Rosado Coelho Ana Teresa Freitas Emmanuela Marchi Laura Moce Pilar Visa John Blackman Northwood Carlo Viti Elisa Borghi Graziella Orefici the BIOHYPO Consortium Ian Morrissey Marco Rinaldo Oggioni 《Antimicrobial agents and chemotherapy》2013,57(8):3488-3497
The MICs and minimum bactericidal concentrations (MBCs) for the biocides benzalkonium chloride and chlorhexidine were determined against 1,602 clinical isolates of Staphylococcus aureus. Both compounds showed unimodal MIC and MBC distributions (2 and 4 or 8 mg/liter, respectively) with no apparent subpopulation with reduced susceptibility. To investigate further, all isolates were screened for qac genes, and 39 of these also had the promoter region of the NorA multidrug-resistant (MDR) efflux pump sequenced. The presence of qacA, qacB, qacC, and qacG genes increased the mode MIC, but not MBC, to benzalkonium chloride, while only qacA and qacB increased the chlorhexidine mode MIC. Isolates with a wild-type norA promoter or mutations in the norA promoter had similar biocide MIC distributions; notably, not all clinical isolates with norA mutations were resistant to fluoroquinolones. In vitro efflux mutants could be readily selected with ethidium bromide and acriflavine. Multiple passages were necessary to select mutants with biocides, but these mutants showed phenotypes comparable to those of mutants selected by dyes. All mutants showed changes in the promoter region of norA, but these were distinct from this region of the clinical isolates. Still, none of the in vitro mutants displayed fitness defects in a killing assay in Galleria mellonella larvae. In conclusion, our data provide an in-depth comparative overview on efflux in S. aureus mutants and clinical isolates, showing also that plasmid-encoded efflux pumps did not affect bactericidal activity of biocides. In addition, current in vitro tests appear not to be suitable for predicting levels of resistance that are clinically relevant. 相似文献
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53.
Francesco Scolari Elisa Delbarba Domenico Santoro Loreto Gesualdo Antonello Pani Nadia Dallera Laila-Yasmin Mani Marisa Santostefano Sandro Feriozzi Marco Quaglia Giuliano Boscutti Angelo Ferrantelli Carmelita Marcantoni Patrizia Passerini Riccardo Magistroni Federico Alberici Gian Marco Ghiggeri Claudio Ponticelli Pietro Ravani for the RI-CYCLO Investigators 《Journal of the American Society of Nephrology : JASN》2021,32(4):972
54.
Romina F. Aromando Elisa M. Heber Verónica A. Trivillin David W. Nigg Amanda E. Schwint María E. Itoiz 《Journal of oral pathology & medicine》2009,38(5):448-454
Objective: The therapeutic success of different boron neutron capture therapy (BNCT) protocols employing the hamster cheek pouch oral cancer model has been previously reported by our laboratory. The aim of this study was to explore potential mechanisms of BNCT‐induced damage to tumor in terms of potential inhibition in DNA synthesis and induction of apoptosis in the tumors that underwent partial remission following application of the different BNCT protocols in this model. Materials and methods: We evaluated DNA synthesis employing incorporation of 5‐bromo‐2′‐deoxyuridine as an end‐point. Apoptosis was evaluated by immunohistochemistry employing the deoxynucleotidyl transferase‐mediated deoxyuridine triphosphate‐biotin nick end‐labeling technique and Bax and Bcl‐2 labeling. These studies were performed in tumors that underwent partial remission 1–30 days post‐BNCT mediated by boronophenylalanine (BPA), GB‐10 (Na210B10H10) or (BPA + GB‐10). Results: BNCT exerted a marked inhibitory effect on DNA synthesis in tumors for all the protocols under study. The inhibitory effect of BPA‐BNCT occurred as soon as 1 day post‐treatment (P < 0.001). Conversely, the effect of GB‐10‐BNCT became apparent 7–14 days after therapy (P < 0.001) and was sustained until killed at 30 days post‐treatment (P < 0.001). (GB‐10 + BPA)‐BNCT exerted a rapid and persistent effect, conceivably because of the combined effect of BNCT mediated by both boron compounds. The apoptosis studies did not show differences between the pre‐treatment group and any of the BNCT groups. Conclusions: One of the mechanisms involved in BNCT‐induced tumor control in our model would be an inhibitory effect on DNA synthesis. Apoptosis does not seem to have a significant role in BNCT‐induced tumor control in our model. 相似文献
55.
Infantile hemangioma is a vascular tumor that occurs in 5–10% of infants of European descent. A defining feature of infantile
hemangioma is the dramatic growth and development into a disorganized mass of blood vessels. Subsequently, a slow spontaneous
involution begins around 1 year of age and continues for 4–6 years. The growth and involution of infantile hemangioma is very
different from other vascular tumors and vascular malformations, which do not regress and can occur at any time during childhood
or adult life. Much has been learned from careful study of the tissue morphology and gene expression patterns during the life-cycle
of hemangioma. Tissue explants and tumor-derived cell populations have provided further insight to unravel the cellular and
molecular basis of infantile hemangioma. A multipotent progenitor cell capable of de novo blood vessel formation has been
isolated from infantile hemangioma, which suggests that this common tumor of infancy, long considered to be a model for pathologic
angiogenesis, may also represent pathologic vasculogenesis. Whether viewed as angiogenesis or vasculogenesis, infantile hemangioma
represents a vascular perturbation during a critical period of post-natal growth, and as such provides a unique opportunity
to decipher mechanisms of human vascular development. 相似文献
56.
Alpha-myosin heavy chain: a sarcomeric gene associated with dilated and hypertrophic phenotypes of cardiomyopathy 总被引:1,自引:0,他引:1
57.
Martínez E Milinkovic A de Lazzari E Ravasi G Blanco JL Larrousse M Mallolas J García F Miró JM Gatell JM 《Lancet》2004,364(9428):65-67
The rise in didanosine concentrations in plasma when given with tenofovir raises concern for a high risk of toxic effects. Recommendations to reduce didanosine dose have been issued, but only for adults weighing more than 60 kg. We reviewed cases of pancreatitis in patients receiving didanosine plus tenofovir, didanosine alone, and tenofovir alone to assess the incidence of and risk factors for pancreatitis. Between Aug 1, 2001, and Nov 30, 2003, five of 185 (2.7%) patients receiving didanosine plus tenofovir, one of 182 (0.5%) on didanosine without tenofovir, and none of 208 on tenofovir without didanosine developed pancreatitis (p=0.016). Co-administration of both drugs versus each of them individually was an independent risk factor for pancreatitis (crude hazard ratio 10.666, 95% CI 1.246-91.294, p=0.031). These results suggest that the risk of pancreatitis is heightened when didanosine and tenofovir are given together. 相似文献
58.
Emi Dika Annalisa Patrizi Annalisa Altimari Michelangelo Fiorentino Michelangelo La Placa Elisa Gruppioni 《Cutaneous and ocular toxicology》2015,34(3):251-253
We describe the occurrence of a giant squamous cell carcinoma in a patient receiving vemurafenib for the treatment of late melanoma mestastases. Although the development of keratoacanthomas and squamous cell carcinomas (SCC) has been described during vemurafenib therapy, most of the reported cases are treated with surgical excision. In the present case, SCC regressed after drug withdrawal. 相似文献
59.
Irene Geisner Angela Mittmann Elisa Sheng Tracy Herring Melissa Lewis Christine Lee 《Addiction Research & Theory》2015,23(3):238-245
Research has documented normative perceptions of others' alcohol use and how these related to increased rates of drinking and related problems among college students. Recently, research has expanded this concept to specific events (21st birthday drinking and tailgating). No studies to date examine the construct of normative perceptions of alcohol use for spring break (SB). SB is a known time of risk for increased alcohol use, and understanding whether students overestimate SB drinking norms, variables that influence norms perceptions (gender, ethnicity and travel) and whether SB norms relate to one's own drinking can inform future prevention and intervention efforts. We extend the literature by examining SB normative perceptions: (1) whether or not these perceptions are accurate and (2) the relationship to students' own drinking and related consequences. A random sample (N?=?1583) of students were asked about their SB drinking, consequences and norm perceptions. Students' SB drinking in this study was lower than their perception of typical student SB drinking (p?<?0.001), and women's perceptions were higher than men's (p?<?0.001). After adjusting for demographics and typical drinking, SB norms were significantly associated with SB drinking among those taking a trip over SB (p?<?0.001). After controlling for SB drinking, SB drinking norms were unrelated to consequences. Similar misperceptions exist for SB drinking. Prevention and intervention efforts aimed at reducing SB drinking and consequences, particularly for those planning a trip, may incorporate SB specific social norms education. 相似文献
60.