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271.
Elisa Cannizzo Aliyah R. Sohani Judith A. Ferry Ephraim P. Hochberg Michael J. Kluk Michelle E. Dorn Craig Sadowski Janessa J. Bucci Adam M. Ackerman Janina A. Longtine Giovanni Carulli Frederic I. Preffer 《Journal of Hematopathology》2009,2(3):163-170
Multiple malignancies may occur in the same patient, and a few reports describe cases with multiple hematologic and non-hematologic neoplasms. We report the case of a patient who showed the sequential occurrence of four different lymphoid neoplasms together with a squamous cell carcinoma of the lung. A 62-year-old man with adenopathy was admitted to the hospital, and lymph node biopsy was positive for low-grade follicular lymphoma. He achieved a partial remission with chemotherapy. Two years later, a PET-CT scan showed a left hilar mass in the lung; biopsy showed a squamous cell carcinoma. Simultaneously, he was diagnosed with diffuse large B cell lymphoma in a neck lymph node; after chemo- and radiotherapy, he achieved a complete response. A restaging PET-CT scan 2 years later revealed a retroperitoneal nodule, and biopsy again showed a low-grade follicular lymphoma, while a biopsy of a cutaneous scalp lesion showed a CD30-positive peripheral T cell lymphoma. After some months, a liver biopsy and a right cervical lymph node biopsy showed a CD30-positive peripheral T cell lymphoma consistent with anaplastic lymphoma kinase-negative anaplastic large cell lymphoma. Flow cytometry and cytogenetic and molecular genetic analysis performed at diagnosis and during the patient’s follow-up confirmed the presence of two clonally distinct B cell lymphomas, while the two T cell neoplasms were confirmed to be clonally related. We discuss the relationship between multiple neoplasms occurring in the same patient and the various possible risk factors involved in their development. 相似文献
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273.
Martha Elisa Vazquez‐Memije Teresa Rizza Maria Chiara Meschini Claudia Nesti Filippo Maria Santorelli Rosalba Carrozzo 《Journal of cellular biochemistry》2009,106(5):878-886
The smallest rotary motor of living cells, F0F1‐ATP synthase, couples proton flow—generated by the OXPHOS system—from the intermembrane space back to the matrix with the conversion of ADP to ATP. While all mutations affecting the multisubunit complexes of the OXPHOS system probably impact on the cell's output of ATP, only mutations in complex V can be considered to affect this output directly. So far, most of the F0F1‐ATP synthase variations have been detected in the mitochondrial ATPase6 gene. In this study, the four most frequent mutations in the ATPase6 gene, namely L156R, L217R, L156P, and L217P, are studied for the first time together, both in primary cells and in cybrid clones. Arginine (“R”) mutations were associated with a much more severe phenotype than Proline (“P”) mutations, in terms of both biochemical activity and growth capacity. Also, a threshold effect in both “R” mutations appeared at 50% mutation load. Different mechanisms seemed to emerge for the two “R” mutations: the F1 seemed loosely bound to the membrane in the L156R mutant, whereas the L217R mutant induced low activity of complex V, possibly the result of a reduced rate of proton flow through the A6 channel. J. Cell. Biochem. 106: 878–886, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
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275.
Izaurralde E 《European journal of cell biology》2002,81(11):577-584
Fully processed mRNAs are exported to the cytoplasm where they direct protein synthesis. A general feature of mRNA export is that it is an active, receptor-mediated process. The mRNA export receptors are thought to recognize and bind to the mRNA-export cargoes either directly or indirectly (via adaptor proteins) and facilitate their translocation across the central channel of the nuclear pore complex (NPC). On the cytoplasmic side of the NPC, the exported mRNA is released and the receptor returns to the nucleoplasm, without the cargo, to initiate additional rounds of export. Recent, studies in yeast and in higher eukaryotes have led to the elucidation of an evolutionarily conserved pathway for the export of bulk mRNA to the cytoplasm. 相似文献
276.
The contribution deals with the phytocenological analysis of theRondeletio correifoliae-Andropogonetum multinervosi, an endemic savanna association occuring on the Siguanea Hills (Sierra de la Siguanea) near the Colony Hotel. 相似文献
277.
beta-lactam antibiotics induce the SOS response and horizontal transfer of virulence factors in Staphylococcus aureus 下载免费PDF全文
Maiques E Ubeda C Campoy S Salvador N Lasa I Novick RP Barbé J Penadés JR 《Journal of bacteriology》2006,188(7):2726-2729
Antibiotics that interfere with DNA replication and cell viability activate the SOS response. In Staphylococcus aureus, the antibiotic-induced SOS response promotes replication and high-frequency horizontal transfer of pathogenicity island-encoded virulence factors. Here we report that β-lactams induce a bona fide SOS response in S. aureus, characterized by the activation of the RecA and LexA proteins, the two master regulators of the SOS response. Moreover, we show that β-lactams are capable of triggering staphylococcal prophage induction in S. aureus lysogens. Consequently, and as previously described for SOS induction by commonly used fluoroquinolone antibiotics, β-lactam-mediated phage induction also resulted in replication and high-frequency transfer of the staphylococcal pathogenicity islands, showing that such antibiotics may have the unintended consequence of promoting the spread of bacterial virulence factors. 相似文献
278.
A Nup133-dependent NPC-anchored network tethers centrosomes to the nuclear envelope in prophase 总被引:1,自引:0,他引:1
Bolhy S Bouhlel I Dultz E Nayak T Zuccolo M Gatti X Vallee R Ellenberg J Doye V 《The Journal of cell biology》2011,195(5):855-871
Maintenance of stable E-cadherin-dependent adhesion is essential for epithelial function. The small GTPase Rac is activated by initial cadherin clustering, but the precise mechanisms underlying Rac-dependent junction stabilization are not well understood. Ajuba, a LIM domain protein, colocalizes with cadherins, yet Ajuba function at junctions is unknown. We show that, in Ajuba-depleted cells, Rac activation and actin accumulation at cadherin receptors was impaired, and junctions did not sustain mechanical stress. The Rac effector PAK1 was also transiently activated upon cell-cell adhesion and directly phosphorylated Ajuba (Thr172). Interestingly, similar to Ajuba depletion, blocking PAK1 activation perturbed junction maintenance and actin recruitment. Expression of phosphomimetic Ajuba rescued the effects of PAK1 inhibition. Ajuba bound directly to Rac·GDP or Rac·GTP, but phosphorylated Ajuba interacted preferentially with active Rac. Rather than facilitating Rac recruitment to junctions, Ajuba modulated Rac dynamics at contacts depending on its phosphorylation status. Thus, a Rac-PAK1-Ajuba feedback loop integrates spatiotemporal signaling with actin remodeling at cell-cell contacts and stabilizes preassembled cadherin complexes. 相似文献
279.
Zakrzewski Martha Wilkins Sarah J. Helman Sheridan L. Brilli Elisa Tarantino Germano Anderson Gregory J. Frazer David M. 《Biometals》2022,35(1):27-38
BioMetals - Iron deficiency is one of the most common nutritional deficiencies worldwide and is often treated with oral iron supplements. However, commonly used supplements, including those based... 相似文献
280.
Elisa Canu Federica Agosta Sebastiano Galantucci Adriano Chiò Nilo Riva Vincenzo Silani Andrea Falini Giancarlo Comi Massimo Filippi 《PloS one》2013,8(12)