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Non-small cell lung cancer (NSCLC) is one of the leading causes of cancer death worldwide. Immunotherapy with immune checkpoint inhibitors (ICI) has significantly improved outcomes in some patients, however 80-85% of patients receiving immunotherapy develop primary resistance, manifesting as a lack of response to therapy. Of those that do have an initial response, disease progression may occur due to acquired resistance. The make-up of the tumour microenvironment (TME) and the interaction between tumour infiltrating immune cells and cancer cells can have a large impact on the response to immunotherapy. Robust assessment of the TME with accurate and reproducible methods is vital to understanding mechanisms of immunotherapy resistance. In this paper we will review the evidence of several methodologies to assess the TME, including multiplex immunohistochemistry, imaging mass cytometry, flow cytometry, mass cytometry and RNA sequencing.
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Postoperative complications following third molar removal may interfere with the daily activities of patients, such as mastication, speech, and sleep. Various novel methods have been developed to reduce this postoperative discomfort, but these have their own advantages and disadvantages. This novel technique, Sunil's minimal access laser (SMAL) technique, aims to minimize the postoperative swelling and pain and improve healing by combining minimal access incision by using a diode laser.
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Abstract This study was undertaken to investígate the resistance phenotypes to macrolide-lincosamide-streptogramin B (MLSb) antibiotics and their associated genotypes in isolates of Staphylococcus aureus. We analyzed one hundred, consecutive, non-duplicate isolates (methicillin-susceptible MSSA, n = 53 and methicillin-resistant MRSA, n =47) obtained from var-ious clinical samples between July 2012 to December 2013. The resistance profile to MLSb antibiotics was determined by phenotypic methods and the resistance genes were detected by PCR assays. All of the isolates were subjected to pulsed-field gel electrophoresis (SmaI-PFGE). The overall prevalence of resistance to MLSb antibiotics was 38% and the resistance phenotype distribution was as follows: cMLSb, 22%; iMLSB, 10%; MSb, 5% and L, 1%. We detected ermA, ermC, ermB and mrsA/B genes in these resistant isolates. The single ermA gene was commonly observed mainly in those with a cMLSb R phenotype, whereas the combination ermA and ermC was more commonly observed in isolates with inducible expression. The patterns of SmaI-PFGE suggest a great genetic diversity in both MRSA and MSSA resistant to MLSb antibiotics. The results demonstrate the local presence of S. aureus resistant to MLSb antibiotics and its most frequently described responsible genes. Some of these isolates, especially those with the iMLSB phenotype, may be associated with therapeutic failure. Therefore, efforts should be directed to the correct detection of all MLSb resistant isolates using appropriate laboratory tests. PFGE results reveal a wide spread of resistance genes rather than the circulation of S. aureus clones resistant to MLSb antibiotics.
Resumen Los objetivos de este estudio fueron investigar en Staphylococcus aureus la presencia de fenotipos resistentes a los antibióticos macrólidos, lincosamidas y estreptograminas tipoB (MLSb) y conocer sus genotipos responsables. Analizamos 100 aislamientos consecutivos, no duplicados (53 sensibles a meticilina [MSSA] y 47 resistentes a meticilina [MRSA]), obtenidos entre 2012 y 2013 a partir de diferentes muestras clínicas. El perfil de resistencia a los antibióticos MLSb fue determinado por métodos fenotípicos y los genes de resistencia se detectaron por PCR. Todos los aislamientos fueron comparados por SmaI-PFGE. La prevalencia global de resistencia a los antibióticos MLSB fue del 38% y la distribución de los fenotipos de resistencia fue la siguiente: cMLSB, 22%; iMLSB, 10%; MSB, 5%; L, 1%. Se detectaron los genes ermA, ermC y mrsA/B en los aislamientos resistentes. El gen ermA se observó, sobre todo, en aislamientos con fenotipo resistente constitutivo R (cMLSB), mientras que la combinación ermA y ermC se detectó principalmente en aislamientos con resistencia inducible (iMLSB). Los patrones de Smal-PFGE sugieren una gran diversidad genética en los aislamientos resistentes a los antibióticos MLSb, tanto MRSA como MSSA. Los resultados demuestran la presencia local de S. aureus resistentes a los antibióticos MLSB y de sus genes responsables más frecuentemente descritos. Estos cultivos, especialmente aquellos con fenotipo resistente iMLSB, pueden asociarse con fallas terapéuticas. Por lo tanto, los esfuerzos deben dirigirse a la correcta detección de todos los cultivos resistentes a MLSB utilizando pruebas de laboratorio adecuadas. Los resultados de Smal-PFGE sugieren una amplia diseminación de genes de resistencia, más que la circulación de clones resistentes a los antibióticos MLSB.
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Humanos , Infecções Estafilocócicas , Farmacorresistência Bacteriana Múltipla , Staphylococcus aureus Resistente à Meticilina , Fenótipo , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/genética , Uruguai , Testes de Sensibilidade Microbiana , Macrolídeos/farmacologia , Estreptogramina B/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Staphylococcus aureus Resistente à Meticilina/genética , Lincosamidas/farmacologia , Centros de Atenção Terciária , Genótipo , Hospitais Públicos , Antibacterianos/farmacologiaRESUMO
BACKGROUND AND AIMS: The role of small bowel neoplasia (SBN) screening in asymptomatic patients with Lynch syndrome (LS) is uncertain. The aim of our study was to assess the effectiveness of screening by capsule endoscopy (CE) in these patients. METHODS: This study was an observational, analytical, and retrospective single-center study within the PRED-IdF network. All consecutive asymptomatic patients older than 35 years-old with confirmed LS and no personal history of SBN who started the screening from 2010-2015 were included. The baseline screening and 24 months follow-up were performed by CE. The CE diagnostic yield (positive tumor or polyp) and accuracy, using the follow-up as gold standard, were evaluated. RESULTS: A total of 150 patients underwent the SBN screening program and 135 (52.7 ± 11.2 years-old, 37.8% male) met the inclusion criteria. The baseline CE diagnostic yield was 4.4% (3 polyps, 3 tumors) and the proximal small bowel was the most common location (n = 4, 66.7%). In total, 87 patients underwent follow-up and the diagnostic yield was 4.6%.Four patients were considered positive at follow-up (2 adenomas, 2 adenocarcinomas). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CE were 60%, 100%, 100%, 96.9%, and 97%, respectively. CONCLUSIONS: CE is an accurate procedure for baseline screening of SBN in LS patients and may be efficient for follow-up procedures. However, the optimal starting age of screening and intervals of follow-up must be clarified.
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Acinetobacter baumannii is a known opportunistic pathogen, dangerous for public health mostly due to its ability to rapidly acquire antibiotic-resistance traits. Its genome was described as characterized by remarkable plasticity, with a high frequency of homologous recombinations and proliferation of Insertion Sequences (IS). The SMAL pulsotype is an A. baumannii strain currently isolated only in Italy, characterized by a low incidence and a high persistence over the years. In this present work, we have conducted a comparative genomic analysis on this clone. The genome of 15 SMAL isolates was obtained and characterized in comparison with 24 other assemblies of evolutionary related isolates. The phylogeny highlighted the presence of a monophyletic clade (named ST78A), which includes the SMAL isolates. ST78A isolates have a low rate of homologous recombination and low gene content variability when compared to two related clades (ST78B and ST49) and to the most common A. baumannii variants worldwide (International Clones I and II). Remarkably, genomes in the ST78A clade present a high number of IS, including classes mostly absent in the other related genomes. Among these IS, one copy of IS66 was found to interrupt the gene comEC/rec2, involved in the acquisition of exogenous DNA. The genomic characterization of SMAL isolates shed light on the surprisingly low genomic plasticity and the high IS proliferation present in this strain. The interruption of the gene comEC/rec2 by an IS in the SMAL genomes brought us to formulate an evolutionary hypothesis according to which the proliferation of IS is slowing the acquisition of exogenous DNA, thus limiting genome plasticity. Such genomic architecture could explain the epidemiological behavior of high persistence and low incidence of the clone and provides an interesting framework to compare ST78 with the highly epidemic International Clones, characterized by high genomic plasticity.
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UNLABELLED: Novel nanomaterials for the intracellular transport of therapeutic cargos have been actively sought to effectively breach cell-membrane barriers. In this study we developed novel self-micellizing anticancer lipid (SMAL)-based pro-apoptotic nanoparticles (NPs) that enhance the accumulation and chemotherapeutic efficacy of oxaliplatin (OL) in colorectal cancer cells (CRCs). We demonstrated that NPs with special affinity to caveolae could be designed and based on this specificity, NPs effectively differentiated between endothelial cells (tumor cells) and epithelial cells, without the need for a cell-specific targeting moiety. We demonstrated a remarkable uptake of OL-loaded SMAL NPs (SMAL-OL) in HCT116 and HT-29 cells via the caveolae-mediated endocytosis (CvME) pathway. The higher accumulation of SMAL-OL in the intracellular environment resulted in a significantly elevated anticancer effect compared to that of free OL. Cell cycle analysis proved G2/M phase arrest, along with substantial presence of cells in the sub-G1 phase. An immunoblot analysis indicated an upregulation of pro-apoptotic markers (Bax; caspase-3; caspase-9; and PARP1) and downregulation of Bcl-xl and the PI3K/AKT/mTOR complex, indicating a possible intrinsic apoptotic signaling pathway. Overall, the ability of SMAL NPs to confer preferential specificity towards the cell surface domain could offer an exciting means of targeted delivery without the need for receptor-ligand-type strategies. STATEMENT OF SIGNIFICANCE: In this work, we developed a novel self-micellizing anticancer lipid (SMAL)-based pro-apoptotic nanoparticles (NPs) that enhance the accumulation and chemotherapeutic efficacy of oxaliplatin (OL) in colorectal cancer cells. We demonstrated that NPs with special affinity to caveolae could be realized and based on this specificity, NPs effectively differentiated between endothelial cells (tumor cells) and epithelial cells, without the need for a cell-specific targeting moiety. In addition, oxaliplatin-loaded SMAL were efficiently endocytosed by the cancer cells and represent a significant breakthrough as an effective drug delivery system with promising potential in cancer therapy. We believe this work holds promising potential for the development of next generation of multifunctional nanocarriers for an exciting means of targeted delivery without the need for receptor-ligand-type strategies.
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Antineoplásicos/uso terapêutico , Cavéolas/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Lipídeos/uso terapêutico , Micelas , Nanopartículas/química , Nanotecnologia/métodos , Compostos Organoplatínicos/uso terapêutico , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Cavéolas/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/patologia , Sinergismo Farmacológico , Endocitose/efeitos dos fármacos , Células HCT116 , Células HT29 , Humanos , Lipídeos/farmacologia , Nanopartículas/ultraestrutura , Compostos Organoplatínicos/farmacologia , Oxaliplatina , Fosfatidilinositol 3-Quinases/metabolismo , Fosfolipídeos/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismoRESUMO
Mutation is the ultimate source of genetic variation and evolution. Mutation accumulation (MA) experiments are an alternative approach to study de novo mutation events directly. We have constructed a resource of Spontaneous Mutation Accumulation Lines (SMAL; http://cefg.uestc.edu.cn/smal), which contains all the current publicly available MA lines identified by high-throughput sequencing. We have relocated and mapped the mutations based on the most recent genome annotations. A total of 5,608 single base mutations and 540 other mutations were obtained and are recorded in the current version of the SMAL database. The integrated data in SMAL provide detailed information that can be used in new theoretical analyses. We believe that the SMAL resource will help researchers better understand the processes of genetic variation and the incidence of disease.