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1.
J Antimicrob Chemother ; 79(5): 1164-1168, 2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38546752

RESUMO

OBJECTIVES: Integrase strand transfer inhibitors (INSTIs) have been recently recommended as the preferred first-line option for antiretroviral treatment initiators in low- and middle-income countries (LMICs) in response to the growing circulation of resistant HIV to non-nucleoside reverse transcriptase inhibitors (NNRTIs). In this study, we estimated the frequency of pretreatment drug resistance (PDR) to INSTIs in West Africa and Southeast Asia. MATERIALS AND METHODS: Using samples collected from 2015 to 2016, and previously used to assessed PI, NRTI and NNRTI resistance, we generated HIV integrase sequences and identified relevant INSTI PDR mutations using the Stanford and ANRS algorithms. RESULTS: We generated 353 integrase sequences. INSTI PDR frequency was low, 1.1% (4/353) overall, ranging from 0% to 6.3% according to country. However, frequency of PDR to any drug class was very high, 17.9% (95% CI: 13.9%-22.3%), and mostly associated with a high level of NNRTI PDR, 9.7%, and a moderate level of NRTI PDR, 5.3%. CONCLUSIONS: Our results support the recent introduction of INSTIs in LMICs to improve treatment outcome in these settings, but also stress the need for effective actions to prevent uncontrolled emergence of drug resistance to this drug class.


Assuntos
Farmacorresistência Viral , Infecções por HIV , Inibidores de Integrase de HIV , Integrase de HIV , HIV-1 , Humanos , África Ocidental/epidemiologia , Sudeste Asiático/epidemiologia , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Infecções por HIV/epidemiologia , Integrase de HIV/genética , Inibidores de Integrase de HIV/farmacologia , Inibidores de Integrase de HIV/uso terapêutico , HIV-1/efeitos dos fármacos , HIV-1/genética , Mutação , Prevalência
2.
Gut ; 72(3): 443-450, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36008101

RESUMO

OBJECTIVE: Despite being in sustained and stable remission, patients with Crohn's disease (CD) stopping anti-tumour necrosis factor α (TNFα) show a high rate of relapse (~50% within 2 years). Characterising non-invasively the biological profiles of those patients is needed to better guide the decision of anti-TNFα withdrawal. DESIGN: Ninety-two immune-related proteins were measured by proximity extension assay in serum of patients with CD (n=102) in sustained steroid-free remission and stopping anti-TNFα (infliximab). As previously shown, a stratification based on time to clinical relapse was used to characterise the distinct biological profiles of relapsers (short-term relapsers: <6 months vs mid/long-term relapsers: >6 months). Associations between protein levels and time to clinical relapse were determined by univariable Cox model. RESULTS: The risk (HR) of mid/long-term clinical relapse was specifically associated with a high serum level of proteins mainly expressed in lymphocytes (LAG3, SH2B3, SIT1; HR: 2.2-4.5; p<0.05), a low serum level of anti-inflammatory effectors (IL-10, HSD11B1; HR: 0.2-0.3; p<0.05) and cellular junction proteins (CDSN, CNTNAP2, CXADR, ITGA11; HR: 0.4; p<0.05). The risk of short-term clinical relapse was specifically associated with a high serum level of pro-inflammatory effectors (IL-6, IL12RB1; HR: 3.5-3.6; p<0.05) and a low or high serum level of proteins mainly expressed in antigen presenting cells (CLEC4A, CLEC4C, CLEC7A, LAMP3; HR: 0.4-4.1; p<0.05). CONCLUSION: We identified distinct blood protein profiles associated with the risk of short-term and mid/long-term clinical relapse in patients with CD stopping infliximab. These findings constitute an advance for the development of non-invasive biomarkers guiding the decision of anti-TNFα withdrawal.


Assuntos
Doença de Crohn , Humanos , Infliximab/uso terapêutico , Doença de Crohn/tratamento farmacológico , Recidiva Local de Neoplasia , Fator de Necrose Tumoral alfa , Anti-Inflamatórios/uso terapêutico , Biomarcadores , Recidiva , Indução de Remissão , Glicoproteínas de Membrana , Receptores Imunológicos , Lectinas Tipo C/uso terapêutico , Peptídeos e Proteínas de Sinalização Intercelular
3.
Lancet Oncol ; 24(2): 162-174, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36623515

RESUMO

BACKGROUND: Poly(ADP-ribose) polymerase (PARP) inhibitors are effective in germline BRCA1 or BRCA2 (BRCA1/2) mutation-associated metastatic breast cancer. However, studies evaluating PARP inhibitors plus platinum-based chemotherapy in germline BRCA1/2-wildtype triple-negative breast cancer are scarce. A large proportion of germline BRCA1/2-wildtype triple-negative breast cancer shows homologous recombination deficiency (HRD), resulting in a BRCA-like phenotype that might render sensitivity to PARP inhibitors. The S1416 trial assessed the efficacy of cisplatin combined with the PARP inhibitor veliparib in three predefined groups of metastatic breast cancer: germline BRCA1/2-mutated, BRCA-like, and non-BRCA-like. METHODS: S1416 was a randomised, double-blind, placebo-controlled, phase 2 trial conducted at 154 community and academic clinical sites across the USA. Eligible patients aged 18 years or older had metastatic or recurrent triple-negative breast cancer or germline BRCA1/2-associated metastatic or recurrent breast cancer, an Eastern Cooperative Oncology Group performance status of 0-2, and had received up to one line of chemotherapy for metastatic disease. Patients were randomly assigned (1:1) via the National Clinical Trials Network open interactive system with dynamic balancing on number of previous cytotoxic regimens for metastatic disease to receive intravenous cisplatin (75 mg/m2, day 1) combined with either veliparib or matching placebo (300 mg orally twice a day, days 1-14) on a 21-day cycle. Investigators, patients, and the sponsors were masked to treatment assignment; the study statisticians were unmasked. Central testing after ran domisation classified patients as having mutated or wildtype germline BRCA1/2. A biomarker panel established a priori was used to classify patients with wildtype germline BRCA1/2 into BRCA-like and non-BRCA-like phenotype groups, with BRCA-like status based on at least one of the biomarkers: genomic instability score (≥42), somatic BRCA1/2 mutations, BRCA1 promoter methylation, or non-BRCA1/2 homologous recombination repair germline mutations. The primary endpoint was investigator-assessed progression-free survival, analysed separately for the three predefined biomarker groups with a prespecified α value for each analysis. Efficacy analyses were done by intention to treat and included all eligible patients. Safety analyses of toxicities attributed to treatment included all patients who received at least one dose of veliparib or placebo. The study is ongoing and registered with ClinicalTrials.gov, NCT02595905. FINDINGS: Between July 7, 2016, and June 15, 2019, 335 patients were enrolled and randomly assigned. 320 patients (n=162 to cisplatin plus veliparib, all women; and n=158 to cisplatin plus placebo, 157 women and one man) were eligible for efficacy evaluation. 247 patients were classified into the three biomarker groups: germline BRCA1/2-mutated (n=37), BRCA-like (n=101), and non-BRCA-like (n=109). 73 patients could not be classified due to missing biomarker information. Median follow-up was 11·1 months (IQR 5·6-20·8). In the germline BRCA1/2-mutated group, median progression-free survival was 6·2 months (95% CI 2·3-9·2) in the cisplatin plus veliparib group and 6·4 months (4·3-8·2) in the cisplatin plus placebo group (HR 0·79 [95% CI 0·38-1·67]; log-rank p=0·54). In the BRCA-like group, median progression-free survival was 5·9 months (95% CI 4·3-7·8) in the cisplatin plus veliparib group versus 4·2 months (2·3-5·0) in the cisplatin plus placebo group (HR 0·57 [95% CI 0·37-0·88]; p=0·010). In the non-BRCA-like group, median progression-free survival was 4·0 months (95% CI 2·5-4·7) in the cisplatin plus veliparib group versus 3·0 months (2·2-4·4) in the cisplatin plus placebo group (HR 0·89 [95% CI 0·60-1·33]; p=0·57). The most common grade 3 or worse adverse events attributed to treatment were neutropenia (71 [46%] of 155 patients in the cisplatin plus veliparib group vs 29 [20%] of 147 in the cisplatin plus placebo group), leukopenia (42 [27%] vs 11 [7%]), anaemia (35 [23%] vs 12 [8%]), and thrombocytopenia (29 [19%] vs four [3%]). Serious adverse events attributed to treatment occurred in 48 (31%) patients in the cisplatin plus veliparib group and 53 (36%) patients in the cisplatin plus placebo group. Treatment-related adverse events led to death in one patient in the cisplatin plus veliparib group (sepsis) and one patient in the cisplatin plus placebo group (acute kidney injury due to cisplatin plus heart failure from previous doxorubicin exposure). INTERPRETATION: The addition of veliparib to cisplatin significantly improved progression-free survival in patients with BRCA-like metastatic triple-negative breast cancer, but not in patients with non-BRCA-like metastatic breast cancer. PARP inhibitors combined with platinum-based chemotherapy should be explored further in BRCA-like triple-negative breast cancer. FUNDING: National Cancer Institute and National Institute of General Medical Sciences (US National Institutes of Health); AbbVie; Myriad Genetics; the Biomarker, Imaging, and Quality of Life Studies Funding Program (awarded by the National Cancer Institute); and The University of Kansas Cancer Center.


Assuntos
Antineoplásicos , Neoplasias de Mama Triplo Negativas , Feminino , Humanos , Cisplatino/efeitos adversos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Inibidores de Poli(ADP-Ribose) Polimerases/efeitos adversos , Qualidade de Vida , Recidiva Local de Neoplasia/patologia , Antineoplásicos/efeitos adversos , Mutação , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Método Duplo-Cego
4.
Molecules ; 28(3)2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36770839

RESUMO

Surfactins are cyclic lipopeptides consisting of a ß-hydroxy fatty acid of variable chain length and a peptide ring of seven amino acids linked together by a lactone bridge, forming the cyclic structure of the peptide chain. These compounds are produced mainly by Bacillus species and are well regarded for their antibacterial, antifungal, and antiviral activities. For their surfactin production profiling, several Bacillus strains isolated from vegetable rhizospheres were identified by their fatty acid methyl ester profiles and were tested against phytopathogen bacteria and fungi. The isolates showed significant inhibition against of E. amylovora, X. campestris, B. cinerea, and F. culmorum and caused moderate effects on P. syringae, E. carotovora, A. tumefaciens, F. graminearum, F. solani, and C. gloeosporioides. Then, an HPLC-HESI-MS/MS method was applied to simultaneously carry out the quantitative and in-depth qualitative characterisations on the extracted ferment broths. More than half of the examined Bacillus strains produced surfactin, and the MS/MS spectra analyses of their sodiated precursor ions revealed a total of 29 surfactin variants and homologues, some of them with an extremely large number of peaks with different retention times, suggesting a large number of variations in the branching of their fatty acid chains.


Assuntos
Bacillus , Bacillus/metabolismo , Verduras/metabolismo , Espectrometria de Massas em Tandem , Rizosfera , Peptídeos Cíclicos/química , Ácidos Graxos/metabolismo , Lipopeptídeos/química , Bacillus subtilis/metabolismo
5.
Chem Biodivers ; 19(5): e202200077, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35349207

RESUMO

A series of novel diaminopyrimidines containing pinane moieties were synthesized via an efficient methodology starting from pinane-based aminoalcohols, aminodiols and 2,4-dichloropyrimidines. Bioassay tests demonstrated that compound 18a displayed much stronger antiproliferative activities against four human cancer cell lines (HeLa, Siha, MDA-MB-231, MCF-7 and A2780) than positive control cisplatin. In particular, compound 22a was found to be selective in inhibiting HeLa cell proliferation with cancer cell growth inhibition values higher than 95 %. Moreover, the in vitro screening of prepared compounds against different bacterial and fungal strains is reported. The results revealed that 12b and 17a, the most promising compounds, displayed selective inhibition for the Gram-positive bacteria (B. subtilis and S. aureus) with percent inhibition values ranging from 75 to 95 % at 10 µg/mL concentration. Both selective inhibition and the in vitro activity values demonstrated that these compounds have the potential to be developed into clinically important therapeutic choices for the treatment of infections caused by B. subtilis and S. aureus.


Assuntos
Anti-Infecciosos , Antineoplásicos , Neoplasias Ovarianas , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Monoterpenos Bicíclicos , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células HeLa , Humanos , Estrutura Molecular , Staphylococcus aureus , Relação Estrutura-Atividade
6.
J Vis ; 21(2): 7, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33576764

RESUMO

We examined whether perception of color saturation and lightness depends on the three-dimensional (3D) shape and surface gloss of surfaces rendered to have different hues. In Experiment 1, we parametrically varied specular roughness of predominantly planar surfaces with different mesoscopic relief heights. The orientation of surfaces was varied relative to the light source and observer. Observers matched perceived lightness and chroma (effectively saturation) using spherical objects rendered using CIE LCH color space. We observed strong interactions between perceived saturation and lightness with changes in surface orientation and surface properties (specular roughness and 3D relief height). Declines in saturation and increases in lightness were observed with increasing specular roughness. Changes in relief height had greater effects on perceived saturation and lightness for blue hues compared with reddish and greenish hues. Experiment 2 found inverse correlations between perceived gloss and specular roughness across conditions. Experiment 3 estimated perceived specular coverage and found that a weighted combination of perceived gloss and specular coverage could account for perceived color saturation and lightness, with different coefficients accounting for the perceptual experience for each of the three hue conditions. These findings suggest that perceived color saturation and lightness depend on the separation of specular highlights from diffuse shading informative of chromatic surface reflectance.


Assuntos
Percepção de Cores/fisiologia , Propriedades de Superfície , Humanos , Imageamento Tridimensional , Luz , Orientação Espacial/fisiologia
7.
Int J Mol Sci ; 22(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073167

RESUMO

Discovery of novel antibacterial agents with new structures, which combat pathogens is an urgent task. In this study, a new library of (+)-neoisopulegol-based O-benzyl derivatives of aminodiols and aminotriols was designed and synthesized, and their antimicrobial activity against different bacterial and fungal strains were evaluated. The results showed that this new series of synthetic O-benzyl compounds exhibit potent antimicrobial activity. Di-O-benzyl derivatives showed high activity against Gram-positive bacteria and fungi, but moderate activity against Gram-negative bacteria. Therefore, these compounds may serve a good basis for antibacterial and antifungal drug discovery. Structure-activity relationships were also studied from the aspects of stereochemistry of the O-benzyl group on cyclohexane ring and the substituent effects on the ring system.


Assuntos
Anti-Infecciosos , Compostos de Benzil , Fungos/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Compostos de Benzil/síntese química , Compostos de Benzil/química , Compostos de Benzil/farmacologia
8.
Gut ; 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33106355

RESUMO

OBJECTIVE: A subset of Crohn's disease (CD) patients experiences mid/long-term remission after infliximab withdrawal. Biomarkers are needed to identify those patients. DESIGN: New biomarkers of relapse were searched in the baseline serum of CD patients stopping infliximab when they were under combined therapy (antimetabolite and infliximab) and stable clinical remission (diSconTinuation in CrOhn's disease patients in stable Remission on combined therapy with Immunosuppressors cohort, n=102). From shotgun proteomics experiment (discovery step), biomarker candidates were identified and further targeted by selected reaction monitoring (verification step). The dataset was stratified to search for markers of short-term (<6 months) or mid/long-term relapse (>6 months). The risk of relapse and the predicting capacity associated with biomarker candidates were evaluated using univariate Cox model and log-rank statistic, respectively. To test their complementary predicting capacity, biomarker candidates were systematically combined in pairs. RESULTS: Distinct biomarker candidates were associated with the risk (HR) of short-term (15 proteins, 2.9

9.
Nat Methods ; 14(11): 1083-1086, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28991892

RESUMO

We present SCENIC, a computational method for simultaneous gene regulatory network reconstruction and cell-state identification from single-cell RNA-seq data (http://scenic.aertslab.org). On a compendium of single-cell data from tumors and brain, we demonstrate that cis-regulatory analysis can be exploited to guide the identification of transcription factors and cell states. SCENIC provides critical biological insights into the mechanisms driving cellular heterogeneity.


Assuntos
Redes Reguladoras de Genes , Análise de Célula Única , Algoritmos , Animais , Encéfalo/metabolismo , Análise por Conglomerados , Perfilação da Expressão Gênica , Humanos , Camundongos
10.
Thromb J ; 18(1): 37, 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33317566

RESUMO

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) support can be life-saving in critically ill COVID-19 patients. However, there are many complications associated with this procedure, including Heparin-induced thrombocytopenia (HIT.) Despite its rarity in ECMO cases, HIT can lead to devastating consequences and is difficult to manage. CASE PRESENTATION: In this report, we present a case of a COVID-19 patient on ECMO support who was diagnosed with HIT and required intensive treatment. Initially, HIT was only suspected due to newly-developed thrombocytopenia and oxygenator dysfunction, with thrombi observed later. Regarding his treatment, since there was no recommended replacement to heparin available to us at the time of diagnosis, we decided to use rivaroxaban temporarily. No adverse events were recorded during that period. The patient was able to make a full recovery. CONCLUSION: HIT may jeopardize patient's care during ECMO. As COVID-19 may bring about a surge in the number of patients requiring ECMO support, we need consented guidance to optimize treatment in this specific situation.

11.
J Antimicrob Chemother ; 74(2): 462-467, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30418575

RESUMO

Background: ART in the developing world has moved to a new era with the WHO recommendation to test and immediately treat HIV-positive individuals. A high frequency of pretreatment HIV drug resistance (PDR) can compromise ART efficacy. Our study presents updated estimates of PDR in seven countries from West Africa (Burkina Faso, Cameroon, Côte d'Ivoire, Mali and Togo) and Southeast Asia (Thailand and Vietnam). Methods: Eligible study participants were adult ART initiators, recruited from December 2015 to November 2016 in major ART clinics in each country. HIV drug resistance (HIVDR) tests were performed for all specimens and interpretation was done using the Stanford algorithm. Results: Overall, 1153 participants were recruited and 1020 nt sequences were generated. PDR frequency among all initiators was 15.9% (95% CI: 13.8%-18.3%) overall, ranging from 9.6% and 10.2% in Burkina Faso and Thailand, respectively, 14.7% in Vietnam, 15.4% in Mali, 16.5% in Côte d'Ivoire and 19.3% in Cameroon, to 24.6% in Togo. The prevalence of NNRTI resistance mutations was 12%; NRTI and PI PDR prevalences were 4% and 3%, respectively. Conclusions: Our study shows that in most countries PDR exceeded 10%, warranting the conduct of nationally representative surveys to confirm this trend. In the meantime, actions to prevent drug resistance, including transition from NNRTIs to more robust drug classes should be urgently implemented.


Assuntos
Farmacorresistência Viral/genética , Infecções por HIV/epidemiologia , HIV-1/efeitos dos fármacos , Adulto , África Ocidental/epidemiologia , Fármacos Anti-HIV/sangue , Sudeste Asiático/epidemiologia , Feminino , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Carga Viral
12.
Nature ; 493(7432): 411-5, 2013 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-23263185

RESUMO

Autism spectrum disorders (ASDs) are an early onset, heterogeneous group of heritable neuropsychiatric disorders with symptoms that include deficits in social interaction skills, impaired communication abilities, and ritualistic-like repetitive behaviours. One of the hypotheses for a common molecular mechanism underlying ASDs is altered translational control resulting in exaggerated protein synthesis. Genetic variants in chromosome 4q, which contains the EIF4E locus, have been described in patients with autism. Importantly, a rare single nucleotide polymorphism has been identified in autism that is associated with increased promoter activity in the EIF4E gene. Here we show that genetically increasing the levels of eukaryotic translation initiation factor 4E (eIF4E) in mice results in exaggerated cap-dependent translation and aberrant behaviours reminiscent of autism, including repetitive and perseverative behaviours and social interaction deficits. Moreover, these autistic-like behaviours are accompanied by synaptic pathophysiology in the medial prefrontal cortex, striatum and hippocampus. The autistic-like behaviours displayed by the eIF4E-transgenic mice are corrected by intracerebroventricular infusions of the cap-dependent translation inhibitor 4EGI-1. Our findings demonstrate a causal relationship between exaggerated cap-dependent translation, synaptic dysfunction and aberrant behaviours associated with autism.


Assuntos
Transtorno Autístico/genética , Transtorno Autístico/fisiopatologia , Fator de Iniciação 4E em Eucariotos/metabolismo , Biossíntese de Proteínas , Sinapses/metabolismo , Sinapses/patologia , Animais , Transtorno Autístico/tratamento farmacológico , Transtorno Autístico/patologia , Comportamento Animal/efeitos dos fármacos , Dendritos/metabolismo , Dendritos/patologia , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação Eucariótico 4G/metabolismo , Feminino , Hipocampo/metabolismo , Hidrazonas , Infusões Intraventriculares , Masculino , Camundongos , Camundongos Transgênicos , Neostriado/metabolismo , Plasticidade Neuronal , Nitrocompostos/administração & dosagem , Nitrocompostos/farmacologia , Nitrocompostos/uso terapêutico , Córtex Pré-Frontal/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Biossíntese de Proteínas/genética , Capuzes de RNA/metabolismo , Tiazóis/administração & dosagem , Tiazóis/farmacologia , Tiazóis/uso terapêutico
13.
Mol Syst Biol ; 12(6): 874, 2016 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-27288397

RESUMO

Reversible modification of the RNAPII C-terminal domain links transcription with RNA processing and surveillance activities. To better understand this, we mapped the location of RNAPII carrying the five types of CTD phosphorylation on the RNA transcript, providing strand-specific, nucleotide-resolution information, and we used a machine learning-based approach to define RNAPII states. This revealed enrichment of Ser5P, and depletion of Tyr1P, Ser2P, Thr4P, and Ser7P in the transcription start site (TSS) proximal ~150 nt of most genes, with depletion of all modifications close to the poly(A) site. The TSS region also showed elevated RNAPII relative to regions further 3', with high recruitment of RNA surveillance and termination factors, and correlated with the previously mapped 3' ends of short, unstable ncRNA transcripts. A hidden Markov model identified distinct modification states associated with initiating, early elongating and later elongating RNAPII. The initiation state was enriched near the TSS of protein-coding genes and persisted throughout exon 1 of intron-containing genes. Notably, unstable ncRNAs apparently failed to transition into the elongation states seen on protein-coding genes.


Assuntos
RNA Polimerase II/metabolismo , RNA Mensageiro/metabolismo , Saccharomyces cerevisiae/genética , Sítios de Ligação , Aprendizado de Máquina , Cadeias de Markov , Fosforilação , RNA Polimerase II/química , RNA Fúngico/metabolismo , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Transcrição Gênica
14.
Bioinformatics ; 31(10): 1614-22, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25573916

RESUMO

MOTIVATION: Reconstructing the topology of gene regulatory networks (GRNs) from time series of gene expression data remains an important open problem in computational systems biology. Existing GRN inference algorithms face one of two limitations: model-free methods are scalable but suffer from a lack of interpretability and cannot in general be used for out of sample predictions. On the other hand, model-based methods focus on identifying a dynamical model of the system. These are clearly interpretable and can be used for predictions; however, they rely on strong assumptions and are typically very demanding computationally. RESULTS: Here, we propose a new hybrid approach for GRN inference, called Jump3, exploiting time series of expression data. Jump3 is based on a formal on/off model of gene expression but uses a non-parametric procedure based on decision trees (called 'jump trees') to reconstruct the GRN topology, allowing the inference of networks of hundreds of genes. We show the good performance of Jump3 on in silico and synthetic networks and applied the approach to identify regulatory interactions activated in the presence of interferon gamma.


Assuntos
Algoritmos , Biologia Computacional/métodos , Árvores de Decisões , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Biologia de Sistemas/métodos , Animais , Bases de Dados Factuais , Macrófagos/metabolismo , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos , Saccharomyces cerevisiae/genética , Fatores de Transcrição/metabolismo
15.
Int J Gynecol Cancer ; 26(2): 301-6, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26745699

RESUMO

OBJECTIVE: The aim of this study was to assess and compare adjuvant chemotherapy followed by either high-dose-rate vaginal vault brachytherapy (VBT) alone or combined with pelvic external beam radiotherapy (EBRT) for International Federation of Gynaecology and Obstetrics stage 1 serous or clear cell (CC) endometrial cancer. METHODS: Between 2006 and 2012, 84 women with stage 1 serous or CC endometrial cancer were evaluated postoperatively for adjuvant treatment at our hospital. More than 80% of patients had pelvic lymphadenectomy. Patients declining or not completing adjuvant treatments were excluded. Twenty-five women received 4 to 6 cycles of carboplatin/paclitaxel followed by EBRT and VBT. Thirty-two women received 6 cycles of carboplatin/paclitaxel followed by VBT. Locoregional control and toxicities were assessed during follow-up. RESULTS: The 3-year disease-free survival and overall survival rates for the VBT group compared with the EBRT + VBT group were 88% versus 84%, P = 0.6, and 100% versus 94%, P = 0.6, respectively. Only 1 patient in the EBRT + VBT group developed a distant recurrence. One patient had grade 3 toxicity (chronic gastrointestinal [GI] toxicity) in the EBRT + VBT group. Acute grade 1-to-2 GI and grade 1 genitourinary (GU) toxicities were less frequent in the VBT group compared with the EBRT + VBT group (P = 0.008 and P = 0.019, respectively). Late GI and GU toxicities were comparable. Grade 1 vaginal toxicity was similar in both groups. No acute or late grade 2 GU or vaginal toxicities were reported. CONCLUSIONS: According to this study, VBT alone seems to be as effective as EBRT and VBT for stage 1 serous and CC endometrial cancer treated with surgery and adjuvant chemotherapy. Furthermore, less acute GI and GU toxicities were seen in the VBT group.


Assuntos
Braquiterapia/estatística & dados numéricos , Carcinoma/radioterapia , Neoplasias do Endométrio/radioterapia , Idoso , Idoso de 80 Anos ou mais , Carcinoma/tratamento farmacológico , Quimioterapia Adjuvante , Neoplasias do Endométrio/tratamento farmacológico , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
16.
J Neurosci ; 34(27): 9034-9, 2014 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-24990923

RESUMO

Memory retrieval, often termed reconsolidation, can render previously consolidated memories susceptible to manipulation that can lead to alterations in memory strength. Although it is known that reconsolidation requires mammalian target of rapamycin complex 1 (mTORC1)-dependent translation, the specific contributions of its downstream effectors in reconsolidation are unclear. Using auditory fear conditioning in mice, we investigated the role of eukaryotic translation initiation factor 4E (eIF4E)-eIF4G interactions and p70 S6 kinase polypeptide 1 (S6K1) in reconsolidation. We found that neither 4EGI-1 (2-[(4-(3,4-dichlorophenyl)-thiazol-2-ylhydrazono)-3-(2-nitrophenyl)]propionic acid), an inhibitor of eFI4E-eIF4G interactions, nor PF-4708671 [2-((4-(5-ethylpyrimidin-4-yl)piperazin-1-yl)methyl)-5-(trifluoromethyl)-1H-benzo[d]imidazole], an inhibitor of S6K1, alone blocked the reconsolidation of auditory fear memory. In contrast, using these drugs in concert to simultaneously block eIF4E-eIF4G interactions and S6K1 immediately after memory reactivation significantly attenuated fear memory reconsolidation. Moreover, the combination of 4EGI-1 and PF-4708671 further destabilized fear memory 10 d after memory reactivation, which was consistent with experiments using rapamycin, an mTORC1 inhibitor. Furthermore, inhibition of S6K1 immediately after retrieval resulted in memory destabilization 10 d after reactivation, whereas inhibition of eIF4E-eIF4G interactions did not. These results indicate that the reconsolidation of fear memory requires concomitant association of eIF4E to eIF4G as well as S6K1 activity and that the persistence of memory at longer intervals after memory reactivation also requires mTORC1-dependent processes that involve S6K1. These findings suggest a potential mechanism for how mTORC1-dependent translation is fine tuned to alter memory persistence.


Assuntos
Aprendizagem da Esquiva/fisiologia , Condicionamento Clássico/fisiologia , Medo/fisiologia , Rememoração Mental/fisiologia , Complexos Multiproteicos/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Estimulação Acústica , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Condicionamento Clássico/efeitos dos fármacos , Sinais (Psicologia) , Eletrochoque , Fator de Iniciação 4E em Eucariotos/antagonistas & inibidores , Fator de Iniciação 4E em Eucariotos/fisiologia , Fator de Iniciação Eucariótico 4G/antagonistas & inibidores , Fator de Iniciação Eucariótico 4G/fisiologia , Hidrazonas , Imidazóis/farmacologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Memória de Longo Prazo/efeitos dos fármacos , Memória de Longo Prazo/fisiologia , Rememoração Mental/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nitrocompostos/farmacologia , Piperazinas/farmacologia , Proteínas Quinases S6 Ribossômicas 90-kDa/deficiência , Proteínas Quinases S6 Ribossômicas 90-kDa/fisiologia , Sirolimo/farmacologia , Tiazóis/farmacologia
17.
Neurobiol Dis ; 83: 67-74, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26306459

RESUMO

Autism spectrum disorder (ASD) is a group of heritable disorders with complex and unclear etiology. Classic ASD symptoms include social interaction and communication deficits as well as restricted, repetitive behaviors. In addition, ASD is often comorbid with intellectual disability. Fragile X syndrome (FXS) is the leading genetic cause of ASD, and is the most commonly inherited form of intellectual disability. Several mouse models of ASD and FXS exist, however the intellectual disability observed in ASD patients is not well modeled in mice. Using the Fmr1 knockout mouse and the eIF4E transgenic mouse, two previously characterized mouse models of fragile X syndrome and ASD, respectively, we generated the eIF4E/Fmr1 double mutant mouse. Our study shows that the eIF4E/Fmr1 double mutant mice display classic ASD behaviors, as well as cognitive dysfunction. Importantly, the learning impairments displayed by the double mutant mice spanned multiple cognitive tasks. Moreover, the eIF4E/Fmr1 double mutant mice display increased levels of basal protein synthesis. The results of our study suggest that the eIF4E/Fmr1 double mutant mouse may be a reliable model to study cognitive dysfunction in the context of ASD.


Assuntos
Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/psicologia , Transtornos Cognitivos/genética , Modelos Animais de Doenças , Fator de Iniciação 4E em Eucariotos/fisiologia , Proteína do X Frágil da Deficiência Intelectual/fisiologia , Memória/fisiologia , Animais , Ansiedade/genética , Comportamento Animal/fisiologia , Condicionamento Clássico/fisiologia , Fator de Iniciação 4E em Eucariotos/genética , Medo/fisiologia , Proteína do X Frágil da Deficiência Intelectual/genética , Hipocampo/metabolismo , Relações Interpessoais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Mutação
18.
J Antimicrob Chemother ; 70(3): 941-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25433009

RESUMO

OBJECTIVES: The objective of this study was to determine the prevalence and correlates of pretreatment drug resistance (PDR) to first-line antiretroviral drugs among people initiating therapy for HIV in Vietnam. METHODS: Blood was collected during November 2009 to October 2010 from people consecutively initiating ART in four purposively selected public outpatient clinics in three Vietnamese cities. At each study site, recruitment lasted for 6-10 months until the target sample size (range 120-130 individuals) had been reached. The viral load was measured in 501 samples; 490 samples (viral load ≥1000 copies/mL) were genotyped using a nucleotide population-based sequencing assay. Self-reported demographic and clinical data were elicited through interviews. We classified drug-resistance-associated mutations (DRMs) according to the 2009 WHO surveillance list. RESULTS: DRMs were identified in 17/490 participants (3.5%; 95% CI 2.2%-5.5%). The prevalence of DRMs was 1.6% (8/490) against NRTIs, 1.6% (8/490) against NNRTIs and 0.8% (4/490) against PIs; three (0.6%) participants were resistant to both NRTIs and NNRTIs. The overall prevalence of PDR to first-line drugs was low [2.7% (13/490); 95% CI 1.6%-4.4%]. The prevalence of PDR to first-line drugs was greater among 198 HIV-infected participants who injected drugs than among 286 participants who reported risks for sexually acquired HIV (4.0% versus 1.4%, P = 0.079). Multivariable logistic regression analysis suggested that PDR to first-line drugs was significantly higher among people who injected drugs (OR = 3.94; 95% CI 1.13-13.68). CONCLUSIONS: With low PDR, first-line ART may be effective in Vietnam and pretreatment genotyping may be unnecessary. Continuing strategies for the prevention and surveillance of antiretroviral resistance are important for maintaining a low prevalence of antiretroviral resistance in Vietnam. The association between resistance and injection drug use warrants further research.


Assuntos
Antirretrovirais/farmacologia , Farmacorresistência Viral , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , Adulto , Estudos de Coortes , Feminino , Genótipo , Infecções por HIV/epidemiologia , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Masculino , Prevalência , Análise de Sequência de DNA , Vietnã/epidemiologia
19.
Am J Physiol Gastrointest Liver Physiol ; 306(3): G229-43, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24464560

RESUMO

Inflammation can contribute to tumor formation; however, markers that predict progression are still lacking. In the present study, the well-established azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced mouse model of colitis-associated cancer was used to analyze microRNA (miRNA) modulation accompanying inflammation-induced tumor development and to determine whether inflammation-triggered miRNA alterations affect the expression of genes or pathways involved in cancer. A miRNA microarray experiment was performed to establish miRNA expression profiles in mouse colon at early and late time points during inflammation and/or tumor growth. Chronic inflammation and carcinogenesis were associated with distinct changes in miRNA expression. Nevertheless, prediction algorithms of miRNA-mRNA interactions and computational analyses based on ranked miRNA lists consistently identified putative target genes that play essential roles in tumor growth or that belong to key carcinogenesis-related signaling pathways. We identified PI3K/Akt and the insulin growth factor-1 (IGF-1) as major pathways being affected in the AOM/DSS model. DSS-induced chronic inflammation downregulates miR-133a and miR-143/145, which is reportedly associated with human colorectal cancer and PI3K/Akt activation. Accordingly, conditioned medium from inflammatory cells decreases the expression of these miRNA in colorectal adenocarcinoma Caco-2 cells. Overexpression of miR-223, one of the main miRNA showing strong upregulation during AOM/DSS tumor growth, inhibited Akt phosphorylation and IGF-1R expression in these cells. Cell sorting from mouse colons delineated distinct miRNA expression patterns in epithelial and myeloid cells during the periods preceding and spanning tumor growth. Hence, cell-type-specific miRNA dysregulation and subsequent PI3K/Akt activation may be involved in the transition from intestinal inflammation to cancer.


Assuntos
Carcinogênese/metabolismo , Colite/metabolismo , Neoplasias do Colo/metabolismo , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Animais , Azoximetano/efeitos adversos , Colite/induzido quimicamente , Colite/genética , Colite/patologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Sulfato de Dextrana , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
20.
J Cell Sci ; 125(Pt 23): 5711-20, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23077177

RESUMO

Na,K-ATPase is a hetero-oligomer of an α- and a ß-subunit. The α-subunit (Na,K-α) possesses the catalytic function, whereas the ß-subunit (Na,K-ß) has cell-cell adhesion function and is localized to the apical junctional complex in polarized epithelial cells. Earlier, we identified two distinct conserved motifs on the Na,K-ß(1) transmembrane domain that mediate protein-protein interactions: a glycine zipper motif involved in the cis homo-oligomerization of Na,K-ß(1) and a heptad repeat motif that is involved in the hetero-oligomeric interaction with Na,K-α(1). We now provide evidence that knockdown of Na,K-ß(1) prevents lumen formation and induces activation of extracellular regulated kinases 1 and 2 (ERK1/2) mediated by phosphatidylinositol 3-kinase in MDCK cells grown in three-dimensional collagen cultures. These cells sustained cell proliferation in an ERK1/2-dependent manner and did not show contact inhibition at high cell densities, as revealed by parental MDCK cells. This phenotype could be rescued by wild-type Na,K-ß(1) or heptad repeat motif mutant of Na,K-ß(1), but not by the glycine zipper motif mutant that abrogates Na,K-ß(1) cis homo-oligomerization. These studies suggest that Na,K-ß(1) cis homo-oligomerization rather than hetero-oligomerization with Na,K-α(1) is involved in epithelial lumen formation. The relevance of these findings to pre-neoplastic lumen filling in epithelial cancer is discussed.


Assuntos
ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Linhagem Celular , Proliferação de Células , Cães , Immunoblotting , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Multimerização Proteica/genética , Multimerização Proteica/fisiologia , ATPase Trocadora de Sódio-Potássio/química
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