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1.
Lancet ; 404(10452): 527-539, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39096924

RESUMO

BACKGROUND: Patients with unfavourable subset cancer of unknown primary (CUP) have a poor prognosis when treated with standard platinum-based chemotherapy. Whether first-line treatment guided by comprehensive genomic profiling (CGP) can improve outcomes is unknown. The CUPISCO trial was designed to inform a molecularly guided treatment strategy to improve outcomes over standard platinum-based chemotherapy in patients with newly diagnosed, unfavourable, non-squamous CUP. The aim of the trial was to compare the efficacy and safety of molecularly guided therapy (MGT) versus standard platinum-based chemotherapy in these patients. This was to determine whether the inclusion of CGP in the initial diagnostic work-up leads to improved outcomes over the current standard of care. We herein report the primary analysis. METHODS: CUPISCO was a phase 2, prospective, randomised, open-label, active-controlled, multicentre trial done at 159 sites in 34 countries outside the USA. Patients with central eligibility review-confirmed disease (acceptable histologies included adenocarcinoma and poorly differentiated carcinoma) and an Eastern Cooperative Oncology Group performance status of 0 or 1, evaluated by CGP, who reached disease control after three cycles of standard first-line platinum-based chemotherapy were randomly assigned 3:1 via a block-stratified randomisation procedure to MGT versus chemotherapy continuation for at least three further cycles. The primary endpoint was investigator-assessed progression-free survival in the intention-to-treat population. The study is registered with ClinicalTrials.gov, NCT03498521, and follow-up is ongoing. FINDINGS: From July 10, 2018, to Dec 9, 2022, 636 (42%) of 1505 screened patients were enrolled. Median follow-up in the treatment period was 24·1 months (IQR 11·6-35·6). Of 438 patients who reached disease control after induction chemotherapy, 436 were randomly assigned: 326 (75%) to the MGT group and 110 (25%) to the chemotherapy group. Median progression-free survival in the intention-to-treat population was 6·1 months (95% CI 4·7-6·5) in the MGT group versus 4·4 months (4·1-5·6) in the chemotherapy group (hazard ratio 0·72 [95% CI 0·56-0·92]; p=0·0079). Related adverse event rates per 100-patient-years at risk were generally similar or lower with MGT versus chemotherapy. INTERPRETATION: In patients with previously untreated, unfavourable, non-squamous CUP who reached disease control after induction chemotherapy, CGP with subsequent MGTs resulted in longer progression-free survival than standard platinum-based chemotherapy. On the basis of these results, we recommend that CGP is performed at initial diagnosis in patients with unfavourable CUP. FUNDING: F Hoffmann-La Roche.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Primárias Desconhecidas , Humanos , Neoplasias Primárias Desconhecidas/tratamento farmacológico , Neoplasias Primárias Desconhecidas/genética , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos Prospectivos , Adulto , Terapia de Alvo Molecular , Intervalo Livre de Progressão , Adenocarcinoma/tratamento farmacológico
2.
N Engl J Med ; 386(1): 24-34, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34986285

RESUMO

BACKGROUND: Lymphocyte-activation gene 3 (LAG-3) and programmed death 1 (PD-1) are distinct inhibitory immune checkpoints that contribute to T-cell exhaustion. The combination of relatlimab, a LAG-3-blocking antibody, and nivolumab, a PD-1-blocking antibody, has been shown to be safe and to have antitumor activity in patients with previously treated melanoma, but the safety and activity in patients with previously untreated melanoma need investigation. METHODS: In this phase 2-3, global, double-blind, randomized trial, we evaluated relatlimab and nivolumab as a fixed-dose combination as compared with nivolumab alone when administered intravenously every 4 weeks to patients with previously untreated metastatic or unresectable melanoma. The primary end point was progression-free survival as assessed by blinded independent central review. RESULTS: The median progression-free survival was 10.1 months (95% confidence interval [CI], 6.4 to 15.7) with relatlimab-nivolumab as compared with 4.6 months (95% CI, 3.4 to 5.6) with nivolumab (hazard ratio for progression or death, 0.75 [95% CI, 0.62 to 0.92]; P = 0.006 by the log-rank test). Progression-free survival at 12 months was 47.7% (95% CI, 41.8 to 53.2) with relatlimab-nivolumab as compared with 36.0% (95% CI, 30.5 to 41.6) with nivolumab. Progression-free survival across key subgroups favored relatlimab-nivolumab over nivolumab. Grade 3 or 4 treatment-related adverse events occurred in 18.9% of patients in the relatlimab-nivolumab group and in 9.7% of patients in the nivolumab group. CONCLUSIONS: The inhibition of two immune checkpoints, LAG-3 and PD-1, provided a greater benefit with regard to progression-free survival than inhibition of PD-1 alone in patients with previously untreated metastatic or unresectable melanoma. Relatlimab and nivolumab in combination showed no new safety signals. (Funded by Bristol Myers Squibb; RELATIVITY-047 ClinicalTrials.gov number, NCT03470922.).


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antígenos CD/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Inibidores de Checkpoint Imunológico/uso terapêutico , Melanoma/tratamento farmacológico , Nivolumabe/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Antígeno B7-H1/metabolismo , Método Duplo-Cego , Feminino , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Masculino , Melanoma/metabolismo , Melanoma/secundário , Pessoa de Meia-Idade , Nivolumabe/efeitos adversos , Intervalo Livre de Progressão , Proteína do Gene 3 de Ativação de Linfócitos
3.
Eur J Clin Microbiol Infect Dis ; 42(8): 1011-1024, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37420129

RESUMO

Extended-spectrum beta-lactamase (ESBL)- and plasmid-mediated cephalosporinase (AmpC)-producing Enterobacterales (ESBL/AmpC-E) are an increasing healthcare problem in both human and veterinary medicine. The aim of this study was to investigate the possible sharing of ESBL/AmpC-E strains between healthy companion animals and humans of the same household in Portugal (PT) and the United Kingdom (UK). In a prospective longitudinal study, between 2018 and 2020, faecal samples were collected from healthy dogs (n=90), cats (n=20) and their cohabiting humans (n=119) belonging to 41 PT and 44 UK households. Samples were screened for the presence of ESBL/AmpC-E and carbapenemase-producing bacteria. Clonal relatedness between animal and human strains was established by using REP-PCR fingerprinting method, followed by whole-genome sequencing (WGS) of selected strains. ESBL/AmpC-E strains were detected in companion animals (PT=12.7%, n=8/63; UK=8.5%, n=4/47) and humans (PT=20.7%, n=12/58; UK=6.6%, n=4/61) in at least one timepoint. REP-PCR identified paired multidrug-resistant ESBL/AmpC-producing Escherichia coli strains from companion animals and owners in two Portuguese households (4.8%) and one UK household (2.3%). WGS analysis of nine E. coli strains from these three households confirmed that interhost sharing occurred only between the two animal-human pairs from Portugal. Three shared strains were identified: one CTX-M-15-producing E. coli strain in a cat-human pair (O15-H33-ST93) and two CTX-M-15- and CTX-M-55/CMY-2-producing E. coli strains, in a dog-human pair (O8:H9-ST410 and O11:H25-ST457, respectively) at different timepoints. These E. coli clonal lineages are human pandemic, highlighting the role of companion animals living in close contact with humans in the dissemination and persistence of antimicrobial resistance in the household environment.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Humanos , Animais , Cães , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Animais de Estimação , Estudos Longitudinais , Portugal/epidemiologia , Estudos Prospectivos , beta-Lactamases/genética , Antibacterianos/farmacologia , Proteínas de Bactérias
4.
Environ Monit Assess ; 195(3): 361, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36735073

RESUMO

The present study focuses on the Tamoios aquifer (Rio de Janeiro State, Brazil), which is under pressure due to receiving a significant volume of urban runoff and sewage. The objective was based on a number of hydrogeochemical and isotope data to assess the aquifer functioning and establishing a conceptual model to evaluate the hydrogeochemical processes. The database consisted of groundwater samples (n = 20) and surface water samples (fluvial, lagoon, and seawater) (n = 4), analyzed for major and trace constituents plus 18O and 2H isotopes. Results demonstrate that most of the groundwater samples were classified as sodium-chloride type in the rainy season and magnesium-chloride type in the dry season. Ion ratios indicated the ion sources and chemical behavior. Groundwater remained with a relatively high salt content throughout the seasons, particularly in the samples from the southern portion of the aquifer. PHREEQC software simulations exposed dolomite and calcite in mostly undersaturated condition and halite subsaturated throughout the year. Hydrogeochemical behavior indicated the salt content in the groundwater was not related to a hypothetical saltwater intrusion and revealed a steady state condition for the groundwater interface. Groundwater samples have a similar isotopic signature and were likely influenced by evaporative effects, indicating a role for the existing ponds in aquifer recharge. Strong free surface evaporation effects, evapotranspiration, and drainage processes in the floodplains probably enhanced the high ionic concentration in the groundwater environment.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Estações do Ano , Cloretos , Brasil , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Água Subterrânea/química , Cloreto de Sódio
5.
Euro Surveill ; 27(44)2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36330821

RESUMO

BackgroundThe emergence of colistin resistance is a One Health antimicrobial resistance challenge worldwide. The close contact between companion animals and humans creates opportunities for transmission and dissemination of colistin-resistant bacteria.AimTo detect potential animal reservoirs of colistin-resistant Escherichia coli and investigate the possible sharing of these bacteria between dogs, cats and their cohabiting humans in the community in Lisbon, Portugal.MethodsA prospective longitudinal study was performed from 2018 to 2020. Faecal samples from dogs and cats either healthy or diagnosed with a skin and soft tissue or urinary tract infection, and their cohabiting humans were screened for the presence of colistin-resistant E. coli. All isolates were tested by broth microdilution against colistin and 12 other antimicrobials. Colistin-resistant isolates were screened for 30 resistance genes, including plasmid-mediated colistin resistance genes (mcr-1 to mcr-9), and typed by multilocus sequence typing. Genetic relatedness between animal and human isolates was analysed by whole genome sequencing.ResultsColistin-resistant E. coli strains harbouring the mcr-1 gene were recovered from faecal samples of companion animals (8/102; 7.8%) and humans (4/125; 3.2%). No difference between control and infection group was detected. Indistinguishable multidrug-resistant E. coli ST744 strains harbouring the mcr-1 gene were found in humans and their dogs in two households.ConclusionsThe identification of identical E. coli strains containing the plasmid-mediated mcr-1 gene in companion animals and humans in daily close contact is of concern. These results demonstrate the importance of the animal-human unit as possible disseminators of clinically important resistance genes in the community setting.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Animais , Gatos/microbiologia , Cães/microbiologia , Humanos , Antibacterianos/farmacologia , Colistina/farmacologia , Farmacorresistência Bacteriana/genética , Escherichia coli , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/veterinária , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Estudos Longitudinais , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Portugal/epidemiologia , Estudos Prospectivos
6.
Lancet Oncol ; 22(2): 198-211, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33476593

RESUMO

BACKGROUND: First-line nivolumab plus ipilimumab has shown improved overall survival in patients with advanced non-small-cell lung cancer (NSCLC). We aimed to investigate whether the addition of a limited course (two cycles) of chemotherapy to this combination would further enhance the clinical benefit. METHODS: This randomised, open-label, phase 3 trial was done at 103 hospitals in 19 countries. Eligible patients were aged 18 years or older with treatment-naive, histologically confirmed stage IV or recurrent NSCLC, and an Eastern Cooperative Oncology Group performance status of 0-1. Patients were randomly assigned (1:1) by an interactive web response system via permuted blocks (block size of four) to nivolumab (360 mg intravenously every 3 weeks) plus ipilimumab (1 mg/kg intravenously every 6 weeks) combined with histology-based, platinum doublet chemotherapy (intravenously every 3 weeks for two cycles; experimental group), or chemotherapy alone (every 3 weeks for four cycles; control group). Randomisation was stratified by tumour histology, sex, and PD-L1 expression. The primary endpoint was overall survival in all randomly assigned patients. Safety was analysed in all treated patients. Results reported here are from a pre-planned interim analysis (when the study met its primary endpoint) and an exploratory longer-term follow-up analysis. This study is active but no longer recruiting patients, and is registered with ClinicalTrials.gov, number NCT03215706. FINDINGS: Between Aug 24, 2017, and Jan 30, 2019, 1150 patients were enrolled and 719 (62·5%) randomly assigned to nivolumab plus ipilimumab with two cycles of chemotherapy (n=361 [50%]) or four cycles of chemotherapy alone (n=358 [50%]). At the pre-planned interim analysis (median follow-up 9·7 months [IQR 6·4-12·8]), overall survival in all randomly assigned patients was significantly longer in the experimental group than in the control group (median 14·1 months [95% CI 13·2-16·2] vs 10·7 months [9·5-12·4]; hazard ratio [HR] 0·69 [96·71% CI 0·55-0·87]; p=0·00065). With 3·5 months longer median follow-up (median 13·2 months [IQR 6·4-17·0]), median overall survival was 15·6 months (95% CI 13·9-20·0) in the experimental group versus 10·9 months (9·5-12·6) in the control group (HR 0·66 [95% CI 0·55-0·80]). The most common grade 3-4 treatment-related adverse events were neutropenia (in 24 [7%] patients in the experimental group vs 32 [9%] in the control group), anaemia (21 [6%] vs 50 [14%]), diarrhoea (14 [4%] vs two [1%]), increased lipase (22 [6%] vs three [1%]), and asthenia (tjree [1%] vs eight [2%]). Serious treatment-related adverse events of any grade occurred in 106 (30%) patients in the experimental group and 62 (18%) in the control group. Seven (2%) deaths in the experimental group (acute kidney failure, diarrhoea, hepatotoxicity, hepatitis, pneumonitis, sepsis with acute renal insufficiency, and thrombocytopenia; one patient each) and six (2%) deaths in the control group (anaemia, febrile neutropenia, pancytopenia, pulmonary sepsis, respiratory failure, and sepsis; one patient each) were treatment related. INTERPRETATION: Nivolumab plus ipilimumab with two cycles of chemotherapy provided a significant improvement in overall survival versus chemotherapy alone and had a favourable risk-benefit profile. These data support this regimen as a new first-line treatment option for patients with advanced NSCLC. FUNDING: Bristol Myers Squibb.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Ipilimumab/administração & dosagem , Nivolumabe/administração & dosagem , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Resultado do Tratamento
7.
Artigo em Inglês | MEDLINE | ID: mdl-31964797

RESUMO

Two multidrug-resistant and carbapenemase-producing Escherichia coli clones of sequence type 410 were isolated from fecal samples of a dog with skin infection on admission to an animal hospital in Portugal and 1 month after discharge. Whole-genome sequencing revealed a 126,409-bp Col156/IncFIA/IncFII multidrug resistance plasmid and a 51,479-bp IncX3 blaOXA-181-containing plasmid. The chromosome and plasmids carried virulence genes characteristic for uropathogenic E. coli, indicating that dogs may carry multidrug-resistant E. coli isolates related to those causing urinary tract infections in humans.


Assuntos
Doenças do Cão/microbiologia , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Escherichia coli Extraintestinal Patogênica/genética , Escherichia coli Extraintestinal Patogênica/isolamento & purificação , beta-Lactamases/genética , Animais , Proteínas de Bactérias/metabolismo , Doenças do Gato/microbiologia , Gatos , Cães , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/metabolismo , Escherichia coli Extraintestinal Patogênica/metabolismo , Escherichia coli Extraintestinal Patogênica/patogenicidade , Fezes/microbiologia , Microbioma Gastrointestinal , Genoma Bacteriano , Filogenia , Plasmídeos , Portugal , Dermatopatias Bacterianas/microbiologia , Dermatopatias Bacterianas/veterinária , Infecções Urinárias/microbiologia , Infecções Urinárias/veterinária , Fatores de Virulência/genética , beta-Lactamases/metabolismo
8.
J Antimicrob Chemother ; 74(3): 594-602, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30535393

RESUMO

OBJECTIVES: To characterize the population structure, antimicrobial resistance and virulence genes of Klebsiella spp. isolated from dogs, cats and humans with urinary tract infections (UTIs). METHODS: Klebsiella spp. from companion animals (n = 27) and humans (n = 77) with UTI were tested by the disc diffusion method against 29 antimicrobials. Resistant/intermediate isolates were tested by PCR for 16 resistance genes. Seven virulence genes were screened for by PCR. All Klebsiella pneumoniae from companion animals and third-generation cephalosporin (3GC)-resistant isolates from humans were typed by MLST. All Klebsiella spp. were compared after PFGE XbaI macro-restriction using Dice/UPGMA with 1.5% tolerance. RESULTS: bla CTX-M-15 was detected in >80% of 3GC-resistant strains. K. pneumoniae high-risk clonal lineage ST15 predominated in companion animal isolates (60%, n = 15/25). Most companion animal ST15 K. pneumoniae belonged to two PFGE clusters (C4, C5) that also included human strains. Companion animal and human ST15-CTX-M-15 K. pneumoniae shared a fimH-1/mrkD/entB/ycfM/kfu virulence profile, with a few (n = 4) also harbouring the yersiniabactin siderophore-encoding genes. The hospital-adapted ST11 K. pneumoniae clonal lineage was detected in a cat (n = 1) and a human (n = 1); both were MDR, had 81.1% Dice/UPGMA similarity and shared several virulence and resistance genes. Two 3GC-resistant ST348 strains with 86.7% Dice/UPGMA similarity were isolated from a cat and a human. CONCLUSIONS: Companion animals with UTI become infected with high-risk K. pneumoniae clonal lineages harbouring resistance and virulence genes similar to those detected in strains from humans. The ST15-CTX-M-15 K. pneumoniae clonal lineage was disseminated in companion animals with UTI. Caution must be applied by companion animal caretakers to avoid the spread of K. pneumoniae high-risk clonal lineages.


Assuntos
Farmacorresistência Bacteriana , Variação Genética , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/veterinária , Klebsiella pneumoniae/classificação , Infecções Urinárias/epidemiologia , Infecções Urinárias/veterinária , Animais , Gatos , Cães , Eletroforese em Gel de Campo Pulsado , Genótipo , Humanos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Tipagem de Sequências Multilocus , Animais de Estimação , Reação em Cadeia da Polimerase , Infecções Urinárias/microbiologia , Fatores de Virulência/genética
9.
J Biol Chem ; 292(29): 12324-12338, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28550086

RESUMO

Leishmaniasis is one of the leading globally neglected diseases, affecting millions of people worldwide. Leishmania infection depends on the ability of insect-transmitted metacyclic promastigotes to invade mammalian hosts, differentiate into amastigotes, and replicate inside macrophages. To counter the hostile oxidative environment inside macrophages, these protozoans contain anti-oxidant systems that include iron-dependent superoxide dismutases (SODs) in mitochondria and glycosomes. Increasing evidence suggests that in addition to this protective role, Leishmania mitochondrial SOD may also initiate H2O2-mediated redox signaling that regulates gene expression and metabolic changes associated with differentiation into virulent forms. To investigate this hypothesis, we examined the specific role of SODA, the mitochondrial SOD isoform in Leishmania amazonensis Our inability to generate L. amazonensis SODA null mutants and the lethal phenotype observed following RNAi-mediated silencing of the Trypanosoma brucei SODA ortholog suggests that SODA is essential for trypanosomatid survival. L. amazonensis metacyclic promastigotes lacking one SODA allele failed to replicate in macrophages and were severely attenuated in their ability to generate cutaneous lesions in mice. Reduced expression of SODA also resulted in mitochondrial oxidative damage and failure of SODA/ΔsodA promastigotes to differentiate into axenic amastigotes. SODA expression above a critical threshold was also required for the development of metacyclic promastigotes, as SODA/ΔsodA cultures were strongly depleted in this infective form and more susceptible to reactive oxygen species (ROS)-induced stress. Collectively, our data suggest that SODA promotes Leishmania virulence by protecting the parasites against mitochondrion-generated oxidative stress and by initiating ROS-mediated signaling mechanisms required for the differentiation of infective forms.


Assuntos
Ferro/metabolismo , Leishmania mexicana/enzimologia , Mitocôndrias/enzimologia , Proteínas de Protozoários/metabolismo , Superóxido Dismutase/metabolismo , Animais , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Células da Medula Óssea/parasitologia , Células da Medula Óssea/patologia , Linhagem Celular , Células Cultivadas , Células Clonais , Feminino , Técnicas de Inativação de Genes , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Leishmania mexicana/crescimento & desenvolvimento , Leishmania mexicana/patogenicidade , Leishmania mexicana/ultraestrutura , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/metabolismo , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/patologia , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Macrófagos/patologia , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Carga Parasitária , Transporte Proteico , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/genética , Interferência de RNA , Superóxido Dismutase/antagonistas & inibidores , Superóxido Dismutase/genética , Virulência
10.
PLoS Pathog ; 12(1): e1005340, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26741360

RESUMO

Iron, an essential co-factor of respiratory chain proteins, is critical for mitochondrial function and maintenance of its redox balance. We previously reported a role for iron uptake in differentiation of Leishmania amazonensis into virulent amastigotes, by a mechanism that involves reactive oxygen species (ROS) production and is independent of the classical pH and temperature cues. Iron import into mitochondria was proposed to be essential for this process, but evidence supporting this hypothesis was lacking because the Leishmania mitochondrial iron transporter was unknown. Here we describe MIT1, a homolog of the mitochondrial iron importer genes mrs3 (yeast) and mitoferrin-1 (human) that is highly conserved among trypanosomatids. MIT1 expression was essential for the survival of Trypanosoma brucei procyclic but not bloodstream forms, which lack functional respiratory complexes. L. amazonensis LMIT1 null mutants could not be generated, suggesting that this mitochondrial iron importer is essential for promastigote viability. Promastigotes lacking one LMIT1 allele (LMIT1/Δlmit1) showed growth defects and were more susceptible to ROS toxicity, consistent with the role of iron as the essential co-factor of trypanosomatid mitochondrial superoxide dismutases. LMIT1/Δlmit1 metacyclic promastigotes were unable to replicate as intracellular amastigotes after infecting macrophages or cause cutaneous lesions in mice. When induced to differentiate axenically into amastigotes, LMIT1/Δlmit1 showed strong defects in iron content and function of mitochondria, were unable to upregulate the ROS-regulatory enzyme FeSOD, and showed mitochondrial changes suggestive of redox imbalance. Our results demonstrate the importance of mitochondrial iron uptake in trypanosomatid parasites, and highlight the role of LMIT1 in the iron-regulated process that orchestrates differentiation of L. amazonensis into infective amastigotes.


Assuntos
Interações Hospedeiro-Parasita/fisiologia , Ferro/metabolismo , Leishmania/patogenicidade , Mitocôndrias/metabolismo , Proteínas de Protozoários/metabolismo , Sequência de Aminoácidos , Animais , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Leishmania/crescimento & desenvolvimento , Leishmania/metabolismo , Leishmaniose , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Proteínas de Protozoários/genética , Virulência
11.
Cell Microbiol ; 19(3)2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27641840

RESUMO

Leishmania is an intracellular protozoan parasite that causes a broad spectrum of clinical manifestations, ranging from self-healing skin lesions to fatal visceralizing disease. As the host cells of choice for all species of Leishmania, macrophages are critical for the establishment of infections. How macrophages contribute to parasite homing to specific tissues and how parasites modulate macrophage function are still poorly understood. In this study, we show that Leishmania amazonensis infection inhibits macrophage roaming motility. The reduction in macrophage speed is not dependent on particle load or on factors released by infected macrophages. L. amazonensis-infected macrophages also show reduced directional migration in response to the chemokine MCP-1. We found that infected macrophages have lower levels of total paxillin, phosphorylated paxillin, and phosphorylated focal adhesion kinase when compared to noninfected macrophages, indicating abnormalities in the formation of signaling adhesion complexes that regulate motility. Analysis of the dynamics of actin polymerization at peripheral sites also revealed a markedly enhanced F-actin turnover frequency in L. amazonensis-infected macrophages. Thus, Leishmania infection inhibits macrophage motility by altering actin dynamics and impairing the expression of proteins that function in plasma membrane-extracellular matrix interactions.


Assuntos
Actinas/metabolismo , Movimento Celular , Leishmania mexicana/patogenicidade , Macrófagos/fisiologia , Macrófagos/parasitologia , Proteína-Tirosina Quinases de Adesão Focal/análise , Macrófagos/química , Paxilina/análise
12.
Mem Inst Oswaldo Cruz ; 113(4): e170345, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29412342

RESUMO

BACKGROUND: Leishmaniasis, one of the most neglected diseases, is a serious public health problem in many countries, including Brazil. Currently available treatments require long-term use and have serious side effects, necessitating the development of new therapeutic interventions. Because translocator protein (TSPO) levels are reduced in Leishmania amazonensis-infected cells and because this protein participates in apoptosis and immunomodulation, TSPO represents a potential target for Leishmania chemotherapy. The present study evaluated PK11195, a ligand of this protein, as an anti-leishmanial agent. OBJECTIVE: To evaluate the leishmanicidal activity of PK11195 against L. amazonensis in infected CBA mouse macrophages in vitro. METHODS: The viability of axenic L. amazonensis, Leishmania major, and Leishmania braziliensis promastigotes was assessed after 48 h treatment with PK11195 (0.2-400 µM). Additionally, intracellular parasite viability was evaluated to determine IC50 values and the number of viable parasites in infected macrophages treated with PK11195 (50-100 µM). Infected macrophages were then treated with PK11195 (25-100 µM) to determine the percentage of L. amazonensis-infected cells and the number of parasites per infected cell. Electron microscopy was used to investigate morphological changes caused by PK11195. The production of free oxygen radicals, nitric oxide, and pro-inflammatory cytokines was also evaluated in infected macrophages treated with PK11195 and primed or not primed with IFN-γ. FINDINGS: Median IC50 values for PK11195 were 14.2 µM for L. amazonensis, 8.2 µM for L. major, and 3.5 µM for L. braziliensis. The selective index value for L. amazonensis was 13.7, indicating the safety of PK11195 for future testing in mammals. Time- and dose-dependent reductions in the percentage of infected macrophages, the number of parasites per infected macrophage, and the number of viable intracellular parasites were observed. Electron microscopy revealed some morphological alterations suggestive of autophagy. Interestingly, MCP-1 and superoxide levels were reduced in L. amazonensis-infected macrophages treated with PK11195. MAIN CONCLUSIONS: PK11195 causes the killing of amastigotes in vitro by mechanisms independent of inflammatory mediators and causes morphological alterations within Leishmania parasites, suggestive of autophagy, at doses that are non-toxic to macrophages. Thus, this molecule has demonstrated potential as an anti-leishmanial agent.


Assuntos
Isoquinolinas/farmacologia , Leishmania braziliensis/efeitos dos fármacos , Leishmania major/efeitos dos fármacos , Leishmania mexicana/efeitos dos fármacos , Macrófagos/parasitologia , Animais , Leishmania braziliensis/ultraestrutura , Leishmania major/ultraestrutura , Leishmania mexicana/ultraestrutura , Dose Letal Mediana , Camundongos , Camundongos Endogâmicos CBA , Microscopia Eletrônica de Transmissão , Testes de Sensibilidade Parasitária , Fatores de Tempo
13.
Odontology ; 106(4): 445-453, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29497867

RESUMO

This retrospective observational study aimed to evaluate and identify the relapse rate after orthognathic surgery for maxillary advancement (Le Fort I maxillary osteotomy) in oral cleft patients through digitized cephalograms and 3D dental models, following 2 years. Lateral cephalograms and dental casts of 17 individuals, enrolled in Orthodontics Department in Hospital of Rehabilitation of Craniofacial Anomalies, were carried out. The digital cephalometric tracings were evaluated in: T1-before surgery, T2-immediate after surgery, T3-6-month to 1-year after surgery. The dental study casts were digitized and evaluated in: F1-before surgery; F2-3-month to 1-year after surgery; F3-1 to 2 years after surgery. The analyses of the dental arches were performed directly on the scanned images. A single examiner previously trained and calibrated performed all the assessments. Repeated measures ANOVA was applied to study the variables and compare the periods, followed by Tukey test to evaluate the statistically significant differences, with level of significance of 5%. The digital cephalogram results showed that the vertical movement statistically differed from T2 to T3 (p = 0.002). The right and left premolar relationship in digitized models revealed that at F2 the individuals exhibited » Class II and Class I, in 29.4 and 23.5% of the cases, respectively; and at F3, Class I, 58.8 and 70.6% of the cases, respectively. The cephalometry showed the relapse in the vertical movement after orthognathic surgery for maxillary advancement, but no relapse in the other evaluated parameters.


Assuntos
Cefalometria , Fissura Palatina/diagnóstico por imagem , Fissura Palatina/cirurgia , Osteotomia de Le Fort , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Imageamento Tridimensional , Masculino , Recidiva
14.
J Craniofac Surg ; 27(8): e790-e791, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28005826

RESUMO

Porous polyethylene implants have been used as an alternative in the treatment of patients with zygomatic and paranasal projections deficiency. These implants promote a facial rejuvenating effect due to the attenuation of the nasal and chin prominences. The advantages of porous polyethylene include biocompatibility, dimensional stability, easy adaptation and fixation, low complication rate, and its availability in different sizes and shapes. A 27-year-old woman presenting vertical deficiency associated with midface hypoplasia was treated with orthognathic surgery. Clockwise rotation and genioplasty were performed. In order to improve facial aesthetics, porous polyethylene implants were placed in the paranasal area, optimizing the facial contour with the correction of the midface projection.


Assuntos
Deformidades Dentofaciais/cirurgia , Face/cirurgia , Procedimentos Cirúrgicos Ortognáticos/métodos , Polietileno , Próteses e Implantes , Adulto , Deformidades Dentofaciais/diagnóstico , Estética , Feminino , Humanos , Porosidade , Desenho de Prótese
15.
Int J Mol Sci ; 17(8)2016 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-27548150

RESUMO

Leishmania is a protozoan parasite that causes a wide range of different clinical manifestations in mammalian hosts. It is a major public health risk on different continents and represents one of the most important neglected diseases. Due to the high toxicity of the drugs currently used, and in the light of increasing drug resistance, there is a critical need to develop new drugs and vaccines to control Leishmania infection. Over the past few years, proteomics has become an important tool to understand the underlying biology of Leishmania parasites and host interaction. The large-scale study of proteins, both in parasites and within the host in response to infection, can accelerate the discovery of new therapeutic targets. By studying the proteomes of host cells and tissues infected with Leishmania, as well as changes in protein profiles among promastigotes and amastigotes, scientists hope to better understand the biology involved in the parasite survival and the host-parasite interaction. This review demonstrates the feasibility of proteomics as an approach to identify new proteins involved in Leishmania differentiation and intracellular survival.


Assuntos
Leishmania/patogenicidade , Proteômica/métodos , Animais , Interações Hospedeiro-Parasita , Humanos , Leishmania/metabolismo , Proteínas de Protozoários/metabolismo
16.
Microbiol Spectr ; 12(4): e0341623, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38446073

RESUMO

An increase in Klebsiella pneumoniae carbapenem-resistant human nosocomial strains is occurring in Europe, namely with the blaOXA-48-like and blaKPC-like genes. We determined the prevalence of carbapenemase-producing Enterobacterales clinical strains in companion animals in Portugal and characterized their mobile genetic elements. Susceptibility data of a consecutive collection of 977 Enterobacterales clinical strains from a Portuguese private veterinary diagnostic laboratory were evaluated (January-December 2020). Additional phenotypical and genotypical assays were performed in a subset of 261 strains with a resistant phenotype. Whole-genome sequencing was performed for carbapenemase-producing strains. The frequency of carbapenemase-producing Enterobacterales clinical strains in companion animals in Portugal was 0.51% (n = 5/977). Thus, five strains were characterized: (i) one OXA-181-producing K. pneumoniae ST273, (ii) two KPC-3-producing K. pneumoniae ST147; (iii) one KPC-3-producing K. pneumoniae ST392; and (iv) one OXA-48-producing E. coli ST127. The blaKPC-3 gene was located on transposon Tn4401d on IncFIA type plasmid for the K. pneumoniae ST147 strains and on a IncN-type plasmid for the K. pneumoniae ST392 strain, while blaOXA-181 gene was located on an IncX3 plasmid. All de novo assembled plasmids and plasmid-encoded transposons harboring carbapenemase genes were homologous to those previously described in the human healthcare. No plasmid replicons were detected on the OXA-48-producing E. coli ST127. The dissemination of carbapenem resistance is occurring horizontally via plasmid spreading from the human high burden carbapenem resistance setting to the companion animal sector. Furthermore, companion animals may act as reservoirs of carbapenem resistance. Implementation of carbapenemase detection methods in routine clinical veterinary microbiology is urgently needed. IMPORTANCE: This is the first study on the prevalence of carbapenemase-producing Enterobacterales (CPE) clinical strains from companion animals in Portugal. Despite the generally low prevalence of CPE in companion animals, it is imperative for veterinary diagnostic laboratories to employ diagnostic methods for carbapenemase detection. The resemblance found in the mobile genetic elements transporting carbapenemase genes between veterinary medicine and human medicine implies a potential circulation within a One Health framework.


Assuntos
Infecções por Klebsiella , Animais de Estimação , Humanos , Animais , Portugal/epidemiologia , Escherichia coli/genética , Proteínas de Bactérias/genética , beta-Lactamases/genética , Klebsiella pneumoniae/genética , Carbapenêmicos/farmacologia , Infecções por Klebsiella/microbiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Testes de Sensibilidade Microbiana
17.
J Immunother Cancer ; 12(2)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38346853

RESUMO

BACKGROUND: In CheckMate 9LA, nivolumab plus ipilimumab with chemotherapy prolonged overall survival (OS) versus chemotherapy regardless of tumor PD-L1 expression or histology. We report updated efficacy and safety in all randomized patients with a minimum 4-year follow-up and an exploratory treatment-switching adjustment analysis in all treated patients who received chemotherapy and subsequent immunotherapy. METHODS: Adults with stage IV/recurrent non-small cell lung cancer (NSCLC), no sensitizing EGFR/ALK alterations, and ECOG performance status ≤1 were randomized 1:1 to nivolumab 360 mg every 3 weeks plus ipilimumab 1 mg/kg every 6 weeks with chemotherapy (two cycles) or chemotherapy (four cycles, with optional maintenance pemetrexed for the nonsquamous population). Assessments included OS, progression-free survival, and objective response rate. Exploratory analyses included efficacy by tumor PD-L1 expression and histology and in patients who discontinued nivolumab plus ipilimumab with chemotherapy due to treatment-related adverse events (TRAEs), and a treatment-switching adjustment analysis using inverse probability of censoring weighting. RESULTS: With a 47.9-month minimum follow-up for OS, nivolumab plus ipilimumab with chemotherapy continued to prolong OS over chemotherapy in all randomized patients (HR 0.74, 95% CI 0.63 to 0.87; 4-year OS rate: 21% versus 16%), regardless of tumor PD-L1 expression (HR (95% CI): PD-L1<1%, 0.66 (0.50 to 0.86) and ≥1%, 0.74 (0.60 to 0.92)) or histology (squamous, 0.64 (0.48 to 0.84) and non-squamous, 0.80 (0.66 to 0.97)). In patients who discontinued all components of nivolumab plus ipilimumab with chemotherapy due to TRAEs (n=61), the 4-year OS rate was 41%. With treatment-switching adjustment for the 36% of patients receiving subsequent immunotherapy in the chemotherapy arm, the estimated HR of nivolumab plus ipilimumab with chemotherapy versus chemotherapy was 0.66 (95% CI 0.55 to 0.80). No new safety signals were observed. CONCLUSIONS: In this 4-year update, patients treated with nivolumab plus ipilimumab with chemotherapy continued to have long-term, durable efficacy benefit over chemotherapy regardless of tumor PD-L1 expression and/or histology. A greater estimated relative OS benefit was observed after adjustment for subsequent immunotherapy use in the chemotherapy arm. These results further support nivolumab plus ipilimumab with chemotherapy as a first-line treatment for patients with metastatic/recurrent NSCLC, including those with tumor PD-L1<1% or squamous histology, populations with high unmet needs.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Adulto , Humanos , Nivolumabe/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/patologia , Ipilimumab/farmacologia , Ipilimumab/uso terapêutico , Antígeno B7-H1/metabolismo , Troca de Tratamento , Neoplasias Pulmonares/patologia , Recidiva Local de Neoplasia
18.
Pharmaceuticals (Basel) ; 17(6)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38931434

RESUMO

In the New World, dogs are considered the main reservoir of visceral leishmaniasis (VL). Due to inefficacies in existing treatments and the lack of an efficient vaccine, dog culling is one of the main strategies used to control disease, making the development of new therapeutic interventions mandatory. We previously showed that Tanespimycin (17-AAG), a Hsp90 inhibitor, demonstrated potential for use in leishmaniasis treatment. The present study aimed to test the safety of 17-AAG in dogs by evaluating plasma pharmacokinetics, dose-proportionality, and the tolerability of 17-AAG in response to a dose-escalation protocol and multiple administrations at a single dose in healthy dogs. Two protocols were used: Study A: four dogs received variable intravenous (IV) doses (50, 100, 150, 200, or 250 mg/m2) of 17-AAG or a placebo (n = 4/dose level), using a cross-over design with a 7-day "wash-out" period; Study B: nine dogs received three IV doses of 150 mg/m2 of 17-AAG administered at 48 h intervals. 17-AAG concentrations were determined by a validated high-performance liquid chromatographic (HPLC) method: linearity (R2 = 0.9964), intra-day precision with a coefficient of variation (CV) ≤ 8%, inter-day precision (CV ≤ 20%), and detection and quantification limits of 12.5 and 25 ng/mL, respectively. In Study A, 17-AAG was generally well tolerated. However, increased levels of liver enzymes-alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transferase (GGT)-and bloody diarrhea were observed in all four dogs receiving the highest dosage of 250 mg/m2. After single doses of 17-AAG (50-250 mg/m2), maximum plasma concentrations (Cmax) ranged between 1405 ± 686 and 9439 ± 991 ng/mL, and the area under the curve (AUC) plotting plasma concentration against time ranged between 1483 ± 694 and 11,902 ± 1962 AUC 0-8 h µg/mL × h, respectively. Cmax and AUC parameters were dose-proportionate between the 50 and 200 mg/m2 doses. Regarding Study B, 17-AAG was found to be well tolerated at multiple doses of 150 mg/m2. Increased levels of liver enzymes-ALT (28.57 ± 4.29 to 173.33 ± 49.56 U/L), AST (27.85 ± 3.80 to 248.20 ± 85.80 U/L), and GGT (1.60 ± 0.06 to 12.70 ± 0.50 U/L)-and bloody diarrhea were observed in only 3/9 of these dogs. After the administration of multiple doses, Cmax and AUC 0-48 h were 5254 ± 2784 µg/mL and 6850 ± 469 µg/mL × h in plasma and 736 ± 294 µg/mL and 7382 ± 1357 µg/mL × h in tissue transudate, respectively. In conclusion, our results demonstrate the potential of 17-AAG in the treatment of CVL, using a regimen of three doses at 150 mg/m2, since it presents the maintenance of high concentrations in subcutaneous interstitial fluid, low toxicity, and reversible hepatotoxicity.

19.
J Infect Public Health ; 16 Suppl 1: 190-193, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37926593

RESUMO

A successful outcome of a post-surgical wound infection management by a carbapenem-resistant Klebsiella pneumoniae is described in a dog. Four multidrug-resistant and carbapenem-resistant Escherichia coli strains belonging to ST410 (n = 1) and ST648 (n = 3) were isolated from faecal samples and nasal swabs of this dog at admission to a veterinary hospital in the United Kingdom, and one month after discharge. Whole-genome sequencing analysis suggests dissemination of a 46,161-bp IncX3 blaNDM-5-carrying plasmid among E. coli strains from the different lineages. In this study, the E. coli ST648 strains were virtually identical to each other (5 SNPs difference) indicating dissemination and persistence of this clone over time and across different anatomical sites in the same dog maybe due to the prolonged antimicrobial therapy. The carbapenemase carrying plasmid also showed homology with other publicly available plasmid sequences from Asian countries. These results suggests that plasmids may be a major vehicle in mediating the dissemination of carbapenem-resistance. Further studies investigating the selection and flow of plasmids carrying important resistance genes amongst companion animals are needed as it may further contaminate other environments posing a threat to public health.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Escherichia coli , Cães , Animais , Escherichia coli/genética , Klebsiella pneumoniae/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , beta-Lactamases/genética , Plasmídeos/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Celulite (Flegmão) , Carbapenêmicos/farmacologia , Testes de Sensibilidade Microbiana
20.
Pathog Dis ; 812023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-37401145

RESUMO

Cutaneous leishmaniasis is an infectious disease that may lead to a single or multiple disseminated cutaneous lesions. The mechanisms involved in Leishmania dissemination to different areas of the skin and the internal organs remain poorly understood. Evidence shows that Very Late Antigen-4 (VLA-4)-dependent phagocyte adhesion is impaired by Leishmania infection, which may be related to the mechanisms of parasite dissemination. We investigated factors potentially associated with decreased VLA-4-mediated adhesion in Leishmania-infected macrophages, including lipid raft-mediated VLA-4 mobilization along the cellular membrane, integrin cluster formation at the cell base (adhesion site), and focal adhesion complex assembly. Phagocytes treated with Methyl-ß-Cyclodextrin (MßCD) demonstrated reduced adhesion, similarly to Leishmania amazonensis-infected J774 cells. Infected and MßCD-treated macrophages presented decreased VLA-4 mobilization to the adhesion plane, as well as reduced integrin clustering. Leishmania amazonensis-infected cells exhibited talin depletion, as well as a decreased mobilization of adhesion complex proteins, such as talin and viculin, which were associated with lower VLA-4 concentrations at the adhesion site and limited cell-spreading. Our results suggest that Leishmania infection may modulate the firm adhesion phase of the cell-spreading process, which could contribute to the bloodstream dissemination of infected cells.


Assuntos
Leishmania mexicana , Leishmania , Leishmaniose Cutânea , Humanos , Integrina alfa4beta1 , Talina , Leishmaniose Cutânea/parasitologia , Análise por Conglomerados
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