Because mutations of splicing factor 3B subunit-1 (SF3B1) have been identified in 4% of pancreatic ductal adenocarcinoma (PDAC) patients, we investigated the activity of new potential inhibitors of ...SF3B1 in combination with gemcitabine, one of the standard drugs, in PDAC cell lines.
One imidazo2,1-
1,3,4thiadiazole derivative (IS1) and three indole derivatives (IS2, IS3 and IS4), selected by virtual screening from an in-house library, were evaluated by the sulforhodamine-B and wound healing assay for their cytotoxic and antimigratory activity in the PDAC cells SUIT-2, Hs766t and Panc05.04, the latter harbouring the SF3B1 mutations. The effects on the splicing pattern of proto-oncogene recepteur d'origine nantais (RON) and the gemcitabine transporter human equilibrative nucleoside transporter-1 (hENT1) were assessed by PCR, while the ability to reduce tumour volume was tested in spheroids of primary PDAC cells.
The potential SF3B1 modulators inhibited PDAC cell proliferation and prompted induction of cell death. All compounds showed an interesting anti-migratory ability, associated with splicing RON/ΔRON shift in SUIT-2 cells after 24 h exposure. Moreover, IS1 and IS4 potentiated the sensitivity to gemcitabine in both conventional 2D monolayer and 3D spheroid cultures, and these results might be explained by the statistically significant increase in hENT1 expression (
< 0.05
. untreated control cells), potentially reversing PDAC chemoresistance.
These results support further studies on new SF3B1 inhibitors and the role of RON/hENT1 modulation to develop effective drug combinations against PDAC.
n-Dodecane and fatty acids were good inducers of cytochrome P450 (CYP) and the ω-hydroxylase of lauric acid, which is a marker for ω-hydroxylation of n-alkanes, in Trichoderma harzianum. A cDNA, ...containing an ORF of 1520 bp, encoding a CYP52 of 520 amino acids, was isolated by RACE. Another n-alkane-inducible CYP was identified by LLC-MS/MS analysis of a microsomal protein band induced by n-dodecane in a library of T. harzianum. This suggests that T. harzianum has a CYP-dependent conversion of alkanes to fatty acids allowing their incorporation into lipids.
The pyrimidine analogue gemcitabine is an established effective agent in the treatment of non-small-cell lung cancer (NSCLC). The present study investigates whether gemcitabine would be synergistic ...with the topoisomerase I inhibitor topotecan against the NSCLC A549 and Calu-6 cells. Cells were treated with gemcitabine and topotecan for 1 h and the type of drug interaction was assessed using the combination index (CI). Cell cycle alterations were analysed by flow cytometry, while apoptosis was examined by the occurrence of DNA internucleosomal fragmentation, nuclear condensation and caspase-3 activation. Moreover, the possible involvement of the PI3K-Akt signalling pathway was investigated by the measurement of Akt phosphorylation. Finally, quantitative, real-time PCR (QRT-PCR) was used to study modulation of the gemcitabine-activating enzyme deoxycytidine kinase (dCK) and the cellular target enzyme ribonucleotide reductase (RR). In results, it was found that simultaneous and sequential topotecan --> gemcitabine treatments were synergistic, while the reverse sequence was antagonistic in both cell lines. DNA fragmentation, nuclear condensation and enhanced caspase-3 activity demonstrated that the drug combination markedly increased apoptosis in comparison with either single agent, while cell cycle analysis showed that topotecan increased cells in S phase. Furthermore, topotecan treatment significantly decreased the amount of the activated form of Akt, and enhanced the expression of dCK (+155.0 and +115.3% in A549 and Calu-6 cells, respectively), potentially facilitating gemcitabine activity. In conclusion, these results indicate that the combination of gemcitabine and topotecan displays schedule-dependent activity in vitro against NSCLC cells. The gemcitabine --> topotecan sequence is antagonistic while drug synergism is obtained with the simultaneous and the sequential topotecan --> gemcitabine combinations, which are associated with induction of decreased Akt phosphorylation and increased dCK expression.
Os discursos sobre as políticas de ações afirmativas suscitaram debates não só no âmbito da política, mas também colocaram em pauta uma questão linguística, qual seja a da nomeação. Do ponto de vista ...da Análise do Discurso, consideramos os processos de nomeação como sendo afetados pelo simbólico, de modo a reclamar uma interpretação acerca desses novos nomes. Neste artigo, propusemos trabalhar com a questão das nomeações negro, preto, mulato, afrodescendente e afro-brasileiro, de modo a verificar como elas significam nesses discursos como dispositivos, produzindo novas configurações identitárias que levam ao silenciamento de determinados lugares de dizer na sociedade.
To report the incidence of peripheral trigeminal nerve posttraumatic impairments and to compare different recovery patterns as observed in consideration of different fracture-related variables within ...12-month follow-up.
Ninety-seven consecutive patients with 103 facial fractures were included involving emergence areas of supraorbital nerve, infraorbital nerve, or the region between the mandibular and mental foramina. Presurgical and postsurgical clinical neurosensory testing sessions were performed in each patient. Results of these assessments were compared within fracture characteristics and different sites of trauma. Statistical analysis (chi-square test) was performed on clinical observations.
The incidence of trigeminal nerve impairments was 70.9% (54.4% in nondisplaced fractures, 88.2% in dislocated fractures, 100% in fractures with a direct nerve injury). Severe impairment was found in direct nerve injures and in many dislocated fractures. Mean recovery time was smaller in nondisplaced fractures than in dislocated fractures. Considering fracture site, the highest incidence of initial trigeminal nerve impairment was found in midfacial nondisplaced fractures. Midfacial fractures had better prognosis than mandibular fractures, and best prognosis was encountered in nondisplaced midfacial fractures. Residual hypoesthesia persisted in 11 sides with direct nerve injury after 12 months and involved tactile and discriminative sensibilities.
Recovery patterns of posttraumatic trigeminal dysfunction are related to site and type of fracture; intraoperative assessment of involvement of nerve bundles within fracture rimes was associated with an incomplete recovery at the 12th month. Impairment of temperature and nociception are highly related to a direct nerve injury.
Ataxia telangiectasia (A-T), a genetic disorder caused by the homozygous mutation of the ATM gene, frequently associates with variable degrees of cellular and humoral immunodeficiency. However, the ...immune defects occurring in patients with A-T are still poorly characterized. Here we show that the T-cell receptor (TCR) variable β (BV)–chain repertoire of 9 A-T patients was restricted by diffuse expansions of some variable genes prevalently occurring within the CD4 subset and clustering to certain TCRBV genes (eg, 5.1, 11, 14, and 23). In addition, the study of the third complementarity-determining region (CDR3) showed, in all patients, significantly altered profiles in most BV genes examined suggesting diffuse oligoclonal expansions. The sequencing of TCR CDR3 regions revealed completely normal V(D)J coding joints and confirmed a reduced diversity of the antigen-receptor repertoire. The B-cell repertoire was similarly restricted and skewed by diffuse oligoclonal expansions with normal V(D)J joints. Thymic output, evaluated by measuring TCR rearrangement excision circles, was extremely low. The majority of peripheral T cells had the phenotype and the function of effector memory cells, indicating that in vivo they are able to respond normally by terminal differentiation to antigenic stimulation. These results indicate that ATM mutation limits the generation of a wide repertoire of normally functioning T and B cells.
The territory of the
Inka once covered parts of the present-day countries of Colombia, Ecuador, Peru, Bolivia, Chile, and Argentina, as their political control spread across South America’s Andean ...region. The site of El Shincal de Quimivil, located in the western part of the province of Catamarca in northwestern Argentina, is thought to have served as one of the most important provincial capitals within this territorial range. This article discusses evidence from excavations conducted in Enclosure 1 of the
Kancha II structure, a typical Inka architectural space located at the foot of one of the site’s artificially terraced hills. The enclosure’s excavation has yielded abundant assemblages of archaeological evidence, including ceramic, botanical, faunal, and lithic materials, as well as a centrally located mortar elevated on a platform of stones. The ceramic assemblages are notable for their diversity of typological styles and a high proportion of Inka-type pottery. Faunal materials include discarded food remains, especially camelid bones, and bone projectile points. Plant macroremains identified as maize (
Zea mays) and algarrobo (
Prosopis sp.) were present in the archaeobotanical assemblages. In terms of architectural analysis, the use of space and the materials excavated notably set this enclosure apart from other areas studied at El Shincal de Quimivil. This unique spatial arrangement is probably directly related to festival events, where El Shincal de Quimivil would have played a central role within the dynamics of the southern Inka provinces. Enclosures such as the one discussed here may have served as lodging for visitors during large gatherings.
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