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1.
Mycoses ; 67(3): e13715, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38477367

RESUMO

BACKGROUND: Invasive pulmonary aspergillosis (IPA) is a relatively common infection in patients with acute myeloid leukaemia (AML), and is associated with high mortality rates. Optimising early detection is key to reduce the burden of IPA in this population. In this retrospective cohort study, we evaluated the added value of baseline chest CT before start of classical induction chemotherapy. METHODS: Adult patients receiving first-line intensive chemotherapy for AML were included if a baseline chest CT scan was available (±7 days). Data were collected from the electronic health record. IPA was classified using the EORTC/MSGERC 2020 consensus definitions. RESULTS: Between 2015 and 2019, 99 patients were included. During first-line treatment, 29/99 (30%) patients developed a probable IPA. Baseline chest CT was abnormal in 61/99 (62%) and 14/61 (23%) patients had typical radiological signs for IPA. An abnormal scan showed a trend towards higher risk for IPA (hazard ratio (HR): 2.12; 95% CI 0.95-4.84). Ground glass opacities were a strong predictor for developing IPA (HR 3.35: 95% CI 1.61-7.00). No probable/proven IPA was diagnosed at baseline; however, a bronchoalveolar lavage (BAL) at baseline was only performed in seven patients. Twelve-week mortality was higher in patients with IPA (7/26, 27% vs. 5/59, 8%; p = .024). CONCLUSION: Baseline chest CT scan could be an asset in the early diagnosis of IPA and contribute to risk estimation for IPA. In patients with an abnormal baseline CT, performing a BAL should be considered more frequently, and not only in patients with radiological findings typical for IPA.


Assuntos
Aspergilose , Aspergilose Pulmonar Invasiva , Leucemia Mieloide Aguda , Adulto , Humanos , Estudos Retrospectivos , Estudos de Coortes , Aspergilose Pulmonar Invasiva/diagnóstico , Tomografia Computadorizada por Raios X , Líquido da Lavagem Broncoalveolar
2.
Microbiol Spectr ; 11(6): e0044923, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37982625

RESUMO

IMPORTANCE: People with cystic fibrosis (pwCF) often suffer from chronic lung infections with Pseudomonas aeruginosa. While antibiotics are still commonly used to treat P. aeruginosa infections, there is a high discordance between in vitro and in vivo antibiotic efficacy, which contributes to suboptimal antibiotic therapy. In the present study, we found that isolates from the same sputum sample had highly diverse antibiotic resistance profiles [based on the minimal inhibitory concentration (MIC)], which may explain the reported discrepancy between in vitro and in vivo antibiotic efficacy. Through systematic analysis, we report that pooling nine isolates per sputum sample significantly decreased intrasample diversity in MIC and influenced clinical interpretation of antibiotic susceptibility tests compared to single isolate testing. Hence, pooling of isolates may offer a solution to obtain a consistent MIC test result and could lead to optimizing antibiotic therapy in pwCF and other infectious diseases where diversity in antibiotic resistance is observed.


Assuntos
Fibrose Cística , Infecções por Pseudomonas , Humanos , Pseudomonas aeruginosa , Fibrose Cística/tratamento farmacológico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Pseudomonas/tratamento farmacológico , Testes de Sensibilidade Microbiana
3.
Antibiotics (Basel) ; 11(5)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35625341

RESUMO

Intra-abdominal infections (IAI) are common in hospitalized patients, both in and outside of the intensive care unit. Management principles include antimicrobial therapy and source control. Typically, these infections are polymicrobial, and intra-operative samples will guide the targeted antimicrobial therapy. Although the use of prophylactic abdominal drains in patients undergoing abdominal surgery is decreasing, the use of drains to treat IAI, both in surgical and non-surgical strategies for abdominal infection, is increasing. In this context, samples from abdominal drains are often used to assist in antimicrobial decision making. In this narrative review, we provide an overview of the current role of abdominal drains in surgery, discuss the importance of biofilm formation in abdominal drains and the mechanisms involved, and review the clinical data on the use of sampling these drains for diagnostic purposes. We conclude that biofilm formation and the colonization of abdominal drains is common, which precludes the use of abdominal fluid to reliably diagnose IAI and identify the pathogens involved. We recommend limiting the use of drains and, when present, avoiding routine microbiological sampling.

4.
PLoS One ; 16(10): e0257939, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34695126

RESUMO

BACKGROUND: Bacterial vaginosis (BV) is the most common gynecological condition in women of reproductive age and associated with adverse pregnancy outcomes. In the Democratic Republic of the Congo (DRC), neonatal mortality rate is as high as 2.8 percent with preterm birth (PTB) and low birth weight (LBW) as leading causes. Because no studies have addressed BV in DRC, we aimed to investigate the prevalence of BV, the risk factors and the association between BV and adverse pregnancy outcomes in a population of pregnant women from Bukavu, DRC. METHODS: A total of 533 pregnant women in the second trimester of pregnancy were recruited in the Provincial Reference Hospital of Bukavu, DRC, between January and October 2017, and followed until delivery. Clinical and sociodemographic data of mother and newborn, and data on (vaginal) hygiene practices, sexual behavior and reproductive history were collected. BV was diagnosed by Nugent scoring of Gram-stained vaginal smears. Two multivariate regression models were built to identify risk factors for BV and to investigate BV as a risk factor for adverse pregnancy outcomes. RESULTS: The prevalence of BV was 26.3% and approximately half of the women with BV were asymptomatic. Independent risk factors for BV were the use of alternatives to water for intravaginal washing, concurrent partners, unemployed status, the presence of vaginal Candida and clay consumption. BV was independently associated with both LBW and PTB of an infant with LBW. CONCLUSION: The prevalence of BV in Bukavu is high but in line with the global average. BV was associated with adverse pregnancy outcomes in our study population. Hence, research on modifiable risk factor-based interventions to reduce the prevalence of BV, and on screening/treatment of BV during antenatal care should be explored to reduce neonatal mortality and morbidity.


Assuntos
Candida/isolamento & purificação , Candidíase Vulvovaginal/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Segundo Trimestre da Gravidez , Nascimento Prematuro/epidemiologia , Vaginose Bacteriana/epidemiologia , Adulto , Candidíase Vulvovaginal/microbiologia , República Democrática do Congo/epidemiologia , Feminino , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido de Baixo Peso , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Cuidado Pré-Natal/métodos , Prevalência , Estudos Prospectivos , Fatores de Risco , Vagina/microbiologia , Esfregaço Vaginal , Vaginose Bacteriana/microbiologia , Adulto Jovem
5.
Clin Chem Lab Med ; 58(4): 597-604, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-31860463

RESUMO

Background Diagnosis of upper urinary tract infections (UTI) is challenging. We evaluated the analytical and diagnostic performance characteristics of renal tubular epithelial cells (RTECs) and transitional epithelial cells (TECs) on the Sysmex UF-5000 urine sediment analyzer. Methods Urinary samples from 506 patients presenting with symptoms of a UTI were collected. Only samples for which a urinary culture was available were included. Analytical (imprecision, accuracy, stability and correlation with manual microscopy) and diagnostic performance (sensitivity and specificity) were evaluated. Results The Sysmex UF-5000 demonstrated a good analytical performance. Depending on the storage time, storage conditions (2-8 °C or 20-25 °C) and urinary pH, RTECs and TECs were stable in urine for at least 4 h. Using Passing-Bablok and Bland-Altman analysis, an acceptable agreement was observed between the manual and automated methods. Compared to TECs, RTECs demonstrated an acceptable diagnostic performance for the diagnosis of upper UTI. Conclusions While TECs do not seem to serve as a helpful marker, increased urinary levels of RTECs add value in the diagnosis of upper UTI and may be helpful in the discrimination between upper and lower UTIs.


Assuntos
Urinálise/métodos , Infecções Urinárias/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Cistite/diagnóstico , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Feminino , Humanos , Túbulos Renais/citologia , Masculino , Pessoa de Meia-Idade , Prostatite/diagnóstico , Pielonefrite/diagnóstico , Curva ROC , Sensibilidade e Especificidade , Urinálise/instrumentação , Urina/química , Urina/microbiologia , Adulto Jovem
6.
BMC Infect Dis ; 19(1): 1061, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31847834

RESUMO

BACKGROUND/OBJECTIVES: Assessing the clinical relevance of non-tuberculous mycobacteria (NTM) isolated from respiratory samples can be challenging. The epidemiology and pathogenicity of NTM species vary geographically. We aimed to outline the clinical relevance and associated radiological patterns of NTM species isolated in Belgium. METHODS: We performed a retrospective multicentre analysis of all patients identified from the laboratory database with > 1 respiratory sample growing NTM from January 2010 through December 2017. We collected clinical, radiological and microbiological data through medical record review and assessed clinical relevance according to ATS/IDSA criteria for NTM pulmonary disease (NTM-PD). RESULTS: Of the 384 unique patients, 60% were male, 56% had a smoking history and 61% had pre-existing lung disease. Mycobacterium avium complex (MAC), M. gordonae and M. xenopi were the most frequently isolated species: 53, 15 and 8% respectively. 43% of patients met ATS/IDSA criteria, of whom 28% presented with fibrocavitary disease. Weight loss, fever, nodular bronchiectatic and fibrocavitary lesions on chest CT, and a positive acid-fast bacilli (AFB) stain were significantly associated with NTM-PD. The species with the highest pathogenic potential were M. abscessus (11/12), M. malmoense (6/7) and M. intracellulare (41/64). CONCLUSION: In our study, MAC was the most commonly isolated NTM species, but M. abscessus and M. malmoense showed the highest probability of being clinically relevant. Clinical relevance varied not only by species but also by radiological findings on chest CT and AFB staining. Clinicians should consider these elements in their treatment decision making. Prospective data including clinical outcome are needed to provide more robust evidence.


Assuntos
Bronquiectasia/complicações , Fibrose Cística/complicações , Infecções por Mycobacterium não Tuberculosas/etiologia , Infecções por Mycobacterium não Tuberculosas/microbiologia , Complexo Mycobacterium avium/isolamento & purificação , Doença Pulmonar Obstrutiva Crônica/complicações , Idoso , Bélgica , Testes Diagnósticos de Rotina , Suscetibilidade a Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
7.
Artigo em Inglês | MEDLINE | ID: mdl-31548884

RESUMO

Background: We report a recurrent outbreak of postoperative infections with extended-spectrum ß-lactamase (ESBL)-producing E. cloacae complex in cardiac surgery patients, describe the outbreak investigation and highlight the infection control measures. Methods: Cases were defined as cardiac surgery patients in Ghent University Hospital who were not known preoperatively to carry ESBL-producing E. cloacae complex and who postoperatively had a positive culture for this multiresistant organism between May 2017 and January 2018. An epidemiological investigation, including a case-control study, and environmental investigation were conducted to identify the source of the outbreak. Clonal relatedness of ESBL-producing E. cloacae complex isolates collected from case patients was assessed using whole-genome sequencing-based studies. Results: Three separate outbreak episodes occurred over the course of 9 months. A total of 8, 4 and 6 patients met the case definition, respectively. All but one patients developed a clinical infection with ESBL-producing E. cloacae complex, most typically postoperative pneumonia. Overall mortality was 22% (4/18). Environmental cultures were negative, but epidemiological investigation pointed to transesophageal echocardiography (TEE) as the outbreak source. Of note, four TEE probes showed a similar pattern of damage, which very likely impeded adequate disinfection. The first and second outbreak episode were caused by the same clone, whereas a different strain was responsible for the third episode. Conclusions: Health professionals caring for cardiac surgery patients and infection control specialists should be aware of TEE as possible infection source. Caution must be exercised to prevent and detect damage of TEE probes.


Assuntos
Surtos de Doenças , Ecocardiografia Transesofagiana/instrumentação , Enterobacter cloacae/isolamento & purificação , Infecções por Enterobacteriaceae/epidemiologia , Equipamentos e Provisões/microbiologia , Complicações Pós-Operatórias/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Serviço Hospitalar de Cardiologia , Estudos de Casos e Controles , Enterobacter cloacae/genética , Infecções por Enterobacteriaceae/mortalidade , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mortalidade , Complicações Pós-Operatórias/mortalidade , Recidiva , Sequenciamento Completo do Genoma , beta-Lactamases/metabolismo
9.
Lancet Respir Med ; 6(10): 782-792, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30076119

RESUMO

BACKGROUND: Invasive pulmonary aspergillosis typically occurs in an immunocompromised host. For almost a century, influenza has been known to set up for bacterial superinfections, but recently patients with severe influenza were also reported to develop invasive pulmonary aspergillosis. We aimed to measure the incidence of invasive pulmonary aspergillosis over several seasons in patients with influenza pneumonia in the intensive care unit (ICU) and to assess whether influenza was an independent risk factor for invasive pulmonary aspergillosis. METHODS: We did a retrospective multicentre cohort study. Data were collected from adult patients with severe influenza admitted to seven ICUs across Belgium and The Netherlands during seven influenza seasons. Patients were older than 18 years, were admitted to the ICU for more than 24 h with acute respiratory failure, had pulmonary infiltrates on imaging, and a confirmed influenza infection based on a positive airway PCR test (influenza cohort). We used logistic regression analyses to determine if influenza was independently associated with invasive pulmonary aspergillosis in non-immunocompromised (ie, no European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group [EORTC/MSG] host factor) influenza-positive patients (influenza case group) compared with non-immunocompromised patients with severe community-acquired pneumonia who had a negative airway influenza PCR test (control group). FINDINGS: Data were collected from patients admitted to the ICU between Jan 1, 2009, and June 30, 2016. Invasive pulmonary aspergillosis was diagnosed in 83 (19%) of 432 patients admitted with influenza (influenza cohort), a median of 3 days after admission to the ICU. The incidence was similar for influenza A and B. For patients with influenza who were immunocompromised, incidence of invasive pulmonary aspergillosis was as high as 32% (38 of 117 patients), whereas in the non-immunocompromised influenza case group, incidence was 14% (45 of 315 patients). Conversely, only 16 (5%) of 315 patients in the control group developed invasive pulmonary aspergillosis. The 90-day mortality was 51% in patients in the influenza cohort with invasive pulmonary aspergillosis and 28% in the influenza cohort without invasive pulmonary aspergillosis (p=0·0001). In this study, influenza was found to be independently associated with invasive pulmonary aspergillosis (adjusted odds ratio 5·19; 95% CI 2·63-10·26; p<0·0001), along with a higher APACHE II score, male sex, and use of corticosteroids. INTERPRETATION: Influenza was identified as an independent risk factor for invasive pulmonary aspergillosis and is associated with high mortality. Future studies should assess whether a faster diagnosis or antifungal prophylaxis could improve the outcome of influenza-associated aspergillosis. FUNDING: None.


Assuntos
Aspergillus , Vírus da Influenza A , Vírus da Influenza B , Influenza Humana/epidemiologia , Aspergilose Pulmonar Invasiva/epidemiologia , APACHE , Idoso , Bélgica/epidemiologia , Feminino , Humanos , Incidência , Influenza Humana/microbiologia , Unidades de Terapia Intensiva/estatística & dados numéricos , Aspergilose Pulmonar Invasiva/microbiologia , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Razão de Chances , Admissão do Paciente/estatística & dados numéricos , Estudos Retrospectivos
10.
J Gynecol Oncol ; 29(1): e8, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29185266

RESUMO

OBJECTIVE: Human papillomavirus (HPV) testing is widely incorporated into cervical cancer screening strategies. Current screening requires pelvic examination for cervical sampling, which may compromise participation. The acceptance could be raised by introducing testing on vaginal swabs. We explored the interchangeability of vaginal swabs and cervical smears for HPV testing, by means of a prospective study conducted in female sex workers (FSWs). Besides, we report on the occurrence of 32 different HPV genotypes in FSW with low-grade squamous intraepithelial lesion (LSIL) or high-grade squamous intraepithelial lesion (HSIL). METHODS: Paired physician-collected vaginal swabs and cervical smears from 303 FSW were tested for HPV using the Abbott RealTime High-Risk HPV assay. Cervical cytology was examined on cervical smears. In case of HSIL/LSIL cytological classification (n=52), both samples were genotyped using INNO-LiPa HPV Genotyping Extra II. RESULTS: The overall prevalence of high-risk (HR)-HPV was 51%. In FSW with HSIL/LSIL cervical cytology, the sensitivity and specificity of vaginal samples for the detection of HR-HPV was 100% and 70% and for probable HR-HPV 100% and 91%. The mean number of genotypes identified in vaginal samples (mean=3.5; 95% confidence interval [CI]=2.8-4.2) was significantly higher than in cervical smear samples (mean=2.6; 95% CI=2.1-3.0) (p=0.001). The most frequently encountered HR-HPV genotypes were HPV16, 31, 51, and 52. CONCLUSION: As our study shows that vaginal swabs are equivalent to cervical smears for the detection of (probable) HR-HPV, vaginal swabs can be used for HPV testing in cervical cancer screening strategies. Given the acceptance of vaginal sampling, this finding offers an opportunity to boost screening coverage.


Assuntos
Colo do Útero/patologia , Testes de DNA para Papilomavírus Humano , Tipagem Molecular , Vagina/patologia , Esfregaço Vaginal , Virologia , Adulto , Colo do Útero/virologia , DNA Viral/análise , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/normas , Feminino , Testes de DNA para Papilomavírus Humano/métodos , Testes de DNA para Papilomavírus Humano/normas , Humanos , Pessoa de Meia-Idade , Tipagem Molecular/métodos , Tipagem Molecular/normas , Teste de Papanicolaou , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Sensibilidade e Especificidade , Profissionais do Sexo , Lesões Intraepiteliais Escamosas Cervicais/diagnóstico , Lesões Intraepiteliais Escamosas Cervicais/virologia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/virologia , Vagina/virologia , Esfregaço Vaginal/métodos , Esfregaço Vaginal/normas , Virologia/métodos , Virologia/normas , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/virologia
11.
Infect Control Hosp Epidemiol ; 38(9): 1062-1069, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28633677

RESUMO

OBJECTIVE To compare different techniques of endoscope sampling to assess residual bacterial contamination. DESIGN Diagnostic study. SETTING The endoscopy unit of an 1,100-bed university hospital performing ~13,000 endoscopic procedures annually. METHODS In total, 4 sampling techniques, combining flushing fluid with or without a commercial endoscope brush, were compared in an endoscope model. Based on these results, sterile physiological saline flushing with or without PULL THRU brush was selected for evaluation on 40 flexible endoscopes by adenosine triphosphate (ATP) measurement and bacterial culture. Acceptance criteria from the French National guideline (<25 colony-forming units [CFU] per endoscope and absence of indicator microorganisms) were used as part of the evaluation. RESULTS On biofilm-coated PTFE tubes, physiological saline in combination with a PULL THRU brush generated higher mean ATP values (2,579 relative light units [RLU]) compared with saline alone (1,436 RLU; P=.047). In the endoscope samples, culture yield using saline plus the PULL THRU (mean, 43 CFU; range, 1-400 CFU) was significantly higher than that of saline alone (mean, 17 CFU; range, 0-500 CFU; P<.001). In samples obtained using the saline+PULL THRU brush method, ATP values of samples classified as unacceptable were significantly higher than those of samples classified as acceptable (P=.001). CONCLUSION Physiological saline flushing combined with PULL THRU brush to sample endoscopes generated higher ATP values and increased the yield of microbial surveillance culture. Consequently, the acceptance rate of endoscopes based on a defined CFU limit was significantly lower when the saline+PULL THRU method was used instead of saline alone. Infect Control Hosp Epidemiol 2017;38:1062-1069.


Assuntos
Trifosfato de Adenosina/análise , Técnicas Bacteriológicas/métodos , Biofilmes/crescimento & desenvolvimento , Endoscópios/microbiologia , Bactérias Gram-Negativas/isolamento & purificação , Cloreto de Sódio/administração & dosagem , Bélgica , Desinfecção/métodos , Contaminação de Equipamentos/prevenção & controle , Escherichia coli/isolamento & purificação , Hospitais Universitários , Humanos , Klebsiella pneumoniae/isolamento & purificação , Pseudomonas aeruginosa , Staphylococcus epidermidis
12.
Leuk Res ; 37(1): 3-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22938940

RESUMO

The process of B-cell development is characterized by the activation of the unfolded protein response. Under certain circumstances, the unfolded protein response can be manipulated in a cell death-inducing way. Therefore, tackling the unfolded protein response might be an attractive strategy in the treatment of diffuse large B-cell lymphomas. Our research showed more basal unfolded protein response activity and differences in the inducibility of ER stress in activated B-cell versus germinal center cell lines. Moreover, the diffuse large B cell lymphoma patient data revealed that the glucose-regulated protein 94 is new potential discriminator for diffuse large B cell lymphoma.


Assuntos
Estresse do Retículo Endoplasmático , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Glicoproteínas de Membrana/fisiologia , Resposta a Proteínas não Dobradas , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Apoptose , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Glicoproteínas de Membrana/análise , Prednisona/administração & dosagem , Vincristina/administração & dosagem
13.
Anticancer Res ; 29(10): 3797-805, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19846911

RESUMO

BACKGROUND: Chronic lymphocytic leukemia (CLL) is an incurable disease with a natural history of increasing resistance to chemotherapy. A novel approach to overcome chemotherapy resistance may be targeting the endoplasmic reticulum (ER). PATIENTS AND METHODS: The involvement of the unfolded protein response (UPR) in the cell killing effect of xanthohumol (X) was examined in 18 patient samples. RESULTS: X-induced apoptosis of CLL cells was accompanied by the induction of glucose-regulated protein of 78 kDa (GRP78) and heat-shock protein of 70 kDa (Hsp70) protein levels and by sustained phosphorylation of the eukaryotic translation initiation factor 2 (eIF2alpha), suggesting the involvement of the ER stress transducer, the double-stranded RNA-activated protein kinase (PKR)-like ER kinase (PERK). The X-box-binding protein 1 (XBP1) mRNA was spliced but no clear activation of activating transcription factor 6 (ATF6) was observed. The proapoptotic outcome was further demonstrated by the up-regulation of CCAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP), down-regulation of myeloid cell leukemia 1 (Mcl-1) and B-cell lymphoma 2 (Bcl-2), cleavage of poly-(ADP)-ribose polymerase (PARP) and processing of caspase-3, -4 and -9. Furthermore, X showed proteasome inhibitory activity. CONCLUSION: X stimulates the proapoptotic arm of the UPR in ex vivo CLL cells, suggesting that ER stress may play an important role during X-induced apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Flavonoides/farmacologia , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Propiofenonas/farmacologia , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Fator 6 Ativador da Transcrição/metabolismo , Clorometilcetonas de Aminoácidos/farmacologia , Apoptose/fisiologia , Inibidores de Caspase , Caspases/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Chaperona BiP do Retículo Endoplasmático , Endorribonucleases/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico/metabolismo , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Proteínas de Membrana/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma , Proteínas Serina-Treonina Quinases/metabolismo , eIF-2 Quinase/metabolismo
14.
Anticancer Res ; 29(2): 605-15, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19331210

RESUMO

Chronic lymphocytic leukaemia remains the most common adult leukaemia in Western countries. In this review we tried to give an overview of the important prognostic markers and the developments in this field. We also reflected about the accumulative character of the disease and the influence of the micro-environment on the CLL cell.


Assuntos
Leucemia Linfocítica Crônica de Células B/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/metabolismo , Prognóstico
15.
Leuk Res ; 33(10): 1335-43, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19297020

RESUMO

There is resurgent interest in glucocorticoids (GCs) in the treatment of poor prognosis chronic lymphocytic leukemia (CLL). Little is known however on how GCs induce apoptosis in CLL. Methylprednisolone (MP) induces apoptosis in ZAP-70 positive CLL more readily than in ZAP-70 negative CLL, which is in contrast to the effects of radiation and chemotherapy. The increased GC sensitivity of ZAP-70+ CLL was studied in relation to the expression status of ZAP-70 and the related signal transducing tyrosine kinase SYK. Both ZAP-70 and SYK were downregulated by GC treatment. Moreover, SYK was dephosphorylated by the phosphatase PTP1B of which the expression and translation levels were induced by GCs. Inhibition of PTP1B successfully restored ZAP-70 expression and SYK phosphorylation but did not interfere with GC-induced apoptosis. Therefore, the downregulation of ZAP-70 and P-SYK per se during treatment with GCs is not sufficient to induce apoptosis, and different mechanisms must therefore be responsible for the increased steroid sensitivity of ZAP-70+ CLL.


Assuntos
Corticosteroides/uso terapêutico , Apoptose , Regulação para Baixo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Proteínas Tirosina Quinases/genética , Proteína-Tirosina Quinase ZAP-70/genética , Anexina A5/metabolismo , Apoptose/efeitos dos fármacos , Clorambucila/uso terapêutico , Citometria de Fluxo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Leucemia Linfocítica Crônica de Células B/enzimologia , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Metilprednisolona/uso terapêutico , Plasmídeos , Prognóstico , Proteínas Tirosina Quinases/efeitos dos fármacos , Proteínas Tirosina Quinases/metabolismo , RNA Mensageiro/genética , RNA Neoplásico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Quinase Syk , Vidarabina/análogos & derivados , Vidarabina/uso terapêutico , Proteína-Tirosina Quinase ZAP-70/efeitos dos fármacos , Proteína-Tirosina Quinase ZAP-70/metabolismo
16.
In Vivo ; 21(2): 215-26, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17436569

RESUMO

In eukaryotic cells, the endoplasmic reticulum (ER) is the principal site for the folding and maturation of transmembrane, secretory and ER-resident proteins. Functions of the ER are affected by various intracellular and extracellular stimuli, which include inhibition of glycosylation, reduction of disulfide bonds, calcium depletion from the ER lumen, impairment of protein transport to the Golgi, and expression of mutated proteins in the ER. Under ER stress, unfolded/misfolded proteins accumulate in the ER lumen, which induces conflicting cellular activities: survival and apoptosis. To cope with this stress, cells activate intracellular signalling pathways, such as the unfolded protein response (UPR) and the ER-associated degradation (ERAD). However, under conditions of severe ER stress or when the UPR has been compromised, the cell may be incapable of maintaining ER homeostasis, which may eventually activate programmed cell death (PCD) pathways. Clinical data support the potential of drugs that inhibit the normal functions and homeostasis of the ER and the proteasome in treatment of malignancies like cancer. It is therefore reasonable to assume that manipulation of ER stress might enhance the efficacy of chemotherapeutic drugs and provide new anticancer targets like the ER and the proteasome.


Assuntos
Antineoplásicos/uso terapêutico , Retículo Endoplasmático/efeitos dos fármacos , Animais , Ciclo Celular/genética , Humanos , Mutação , Neoplasias/tratamento farmacológico , Neoplasias/genética , Dobramento de Proteína , Estresse Fisiológico , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
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