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1.
J Hum Evol ; 170: 103237, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35988385

RESUMO

The Abocador de Can Mata (ACM) composite stratigraphic sequence (els Hostalets de Pierola, Vallès-Penedès Basin, NE Iberian Peninsula) has yielded a diverse primate assemblage from the late Aragonian (Middle to Late Miocene). Detailed litho-, bio-, and magnetostratigraphic control has enabled an accurate dating of these fossil remains. Comparable data, however, were lacking for the nearby locality of Can Mata 1 (CM1), which yielded a dryopithecine canine of a female individual. Given the lack of hipparionin equids and giraffids, CM1 has been correlated to the latest Aragonian (Mammal Neogene [MN] zone MN7+8). Here we revise the age of CM1 based on fieldwork and associated paleomagnetic samplings undertaken in 2018-2021. Our results extend the ACM composite sequence upward and indicate that CM1 correlates to the earliest Vallesian (MN9). The updated ACM sequence has a thickness of ∼300 m and comprises 12 magnetozones correlated to subchrons C5Ar.1r to C5n.2n (∼12.6-11.1 Ma; latest MN6 to earliest MN9, late Aragonian to earliest Vallesian). CM1 is correlated to C5r.1r (11.146-11.056 Ma), with an interpolated age of 11.11 Ma, thus postdating the dispersal of hipparionin horses into the Vallès-Penedès Basin-which is correlated to the previous subchron C5r.1n, with an interpolated age of 11.18 Ma, and by definition marks the beginning of the Vallesian. CM1 also minimally postdates the earliest record of giraffids at ACM-representing their earliest well-dated occurrence in the basin-being correlated to C5r.1n with an interpolated age of 11.11 Ma. We conclude that CM1 has an earliest Vallesian (MN9) age of ∼11.1 Ma, intermediate between the Aragonian dryopithecins and the Vallesian hispanopithecins. Ongoing paleontological surveillance at ACM thus offers the prospect to yield additional earliest Vallesian ape remains, which are essential to clarify their taxonomic allocation as well as to confirm whether hispanopithecins evolved locally from dryopithecins rather than immigrating from elsewhere during MN9.


Assuntos
Hominidae , Animais , Cães , Feminino , Fósseis , Cavalos , Mamíferos , Paleontologia , Primatas , Répteis
2.
Int J Mol Sci ; 22(6)2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33809032

RESUMO

Iron is essential for multiple bacterial processes and is thus required for host colonization and infection. The antimicrobial activity of multiple iron chelators and gallium-based therapies against different bacterial species has been characterized in preclinical studies. In this review, we provide a synthesis of studies characterizing the antimicrobial activity of the major classes of iron chelators (hydroxamates, aminocarboxylates and hydroxypyridinones) and gallium compounds. Special emphasis is placed on recent in-vitro and in-vivo studies with the novel iron chelator DIBI. Limitations associated with iron chelation and gallium-based therapies are presented, with emphasis on limitations of preclinical models, lack of understanding regarding mechanisms of action, and potential host toxicity. Collectively, these studies demonstrate potential for iron chelators and gallium to be used as antimicrobial agents, particularly in combination with existing antibiotics. Additional studies are needed in order to characterize the activity of these compounds under physiologic conditions and address potential limitations associated with their clinical use as antimicrobial agents.


Assuntos
Infecções Bacterianas/tratamento farmacológico , Gálio/uso terapêutico , Quelantes de Ferro/uso terapêutico , Ferro/metabolismo , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Bactérias/patogenicidade , Infecções Bacterianas/microbiologia , Farmacorresistência Bacteriana , Humanos , Ácidos Hidroxâmicos/química , Ácidos Hidroxâmicos/uso terapêutico , Ferro/química , Quelantes de Ferro/química , Testes de Sensibilidade Microbiana
3.
Clin Infect Dis ; 68(11): 1894-1903, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-30239624

RESUMO

BACKGROUND: Vaccination is the primary method for preventing influenza respiratory virus infection (RVI). Although the influenza vaccine is able to achieve serological responses in some allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients, its clinical benefits are still uncertain. METHODS: In this prospective, cross-sectional study, we retrospectively analyzed the effect of inactivated trivalent influenza vaccination on the prevalence of influenza RVI in a consecutive cohort of 136 allo-HSCT adult recipients who developed 161 RVI over 5 flu seasons (from 2013 to 2018). Respiratory viruses in upper- and/or lower-respiratory tract specimens were tested using multiplex polymerase chain reaction panel assays. RESULTS: Overall, we diagnosed 74 episodes (46%) of influenza RVI in 70 allo-HSCT recipients. Influenza RVI occurred in 51% of the non-vaccinated compared to 36% of the vaccinated recipients (P = .036). A multivariate analysis showed that influenza vaccination was associated with a lower prevalence of influenza RVI (odds ratio [OR] 0.39, P = .01). A multivariate risk factor analysis of lower-respiratory tract disease (LRTD) identified 2 conditions associated with the probability of influenza RVI progression: influenza vaccination (OR 0.12, 95% confidence interval [CI] 0.014-1, P = .05) and a high-risk immunodeficiency score (OR 36, 95% CI 2.26-575, P = .011). Influenza vaccination was also associated with a lower likelihood of an influenza-related hospital admission (14% vs 2%, P = .04). CONCLUSIONS: This study shows that influenza vaccination may have a clinical benefit in allo-HSCT recipients with virologically-confirmed RVI, in terms of a lower influenza RVI prevalence, slower LRTD progression, and lower likelihood of hospital admission.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Vacinação/estatística & dados numéricos , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Hospitalização , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Espanha , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
4.
Med Microbiol Immunol ; 208(3-4): 405-414, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30911925

RESUMO

Cytomegalovirus (CMV) DNAemia occurs frequently in CMV-seropositive allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients, and usually results from reactivation of latent infection established in the recipient. Predicting the occurrence of CMV DNAemia may be helpful in managing CMV infection in allo-HSCT recipients. Here, the kinetics of several inflammatory biomarkers in plasma were characterized and assessed for their potential value in anticipating the development and features of active CMV infection in allo-HSCT recipients, as documented using real-time PCR assays. The cohort consisted of 46 non-consecutive adult patients who underwent T-cell replete allo-HSCT at our center. Plasma levels of C-reactive protein (CRP), soluble tumor necrosis factor receptor type 2 (sTNF-R2), transforming growth factor-ß1 (TGF-ß1), and interferon-inducible protein 10 (IP-10/CXCL10) were measured in consecutive specimens obtained from conditioning either by nephelometry (CRP) or by specific immunoassays (the rest). Of the 46 patients, 22 had a first episode of CMV DNAemia at a median of 34 days after allo-HSCT (range, day 19-day 50). We found that both the TGF-ß1 area under a curve (AUC) and peak levels were significantly lower in patients who subsequently developed CMV DNAemia than in patients with no CMV DNAemia. Interestingly, CRP but not TGF-ß1 AUC and peak levels predicted the occurrence of CMV DNAemia episodes requiring preemptive antiviral therapy. The data presented herein suggest that kinetics of inflammatory biomarkers in plasma might be useful to anticipate post-engraftment CMV DNAemia episodes and predict the need for preemptive antiviral therapy in allo-HSCT recipients.


Assuntos
Biomarcadores/sangue , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , DNA Viral/sangue , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Fatores Imunológicos/sangue , Humanos , Imunoensaio , Reação em Cadeia da Polimerase em Tempo Real , Transplantados , Transplante Homólogo/efeitos adversos
5.
J Clin Microbiol ; 56(5)2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29540457

RESUMO

The potential impact of routine real-time PCR testing of respiratory specimens from patients with presumptive tuberculosis in terms of diagnostic accuracy and time to tuberculosis treatment inception in low-prevalence settings remains largely unexplored. We conducted a prospective intervention cohort study. Respiratory specimens from 1,020 patients were examined by acid-fast bacillus smear microscopy, tested by a real-time Mycobacterium tuberculosis complex PCR assay (Abbott RealTime MTB PCR), and cultured in mycobacterial media. Seventeen patients tested positive by PCR (5 were acid-fast bacillus smear positive and 12 acid-fast bacillus smear negative), and Mycobacterium tuberculosis was recovered from cultures for 12 of them. Patients testing positive by PCR and negative by culture (n = 5) were treated and deemed to have responded to antituberculosis therapy. There were no PCR-negative/culture-positive cases, and none of the patients testing positive for nontuberculous mycobacteria (n = 20) yielded a positive PCR result. The data indicated that routine testing of respiratory specimens from patients with presumptive tuberculosis by the RealTime MTB PCR assay improves the tuberculosis diagnostic yield and may reduce the time to antituberculosis treatment initiation. On the basis of our data, we propose a novel mycobacterial laboratory algorithm for tuberculosis diagnosis.


Assuntos
Técnicas Bacteriológicas/métodos , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Tuberculose Pulmonar/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antituberculosos/uso terapêutico , Feminino , Humanos , Masculino , Microscopia/métodos , Pessoa de Meia-Idade , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/genética , Estudos Prospectivos , Fatores de Tempo , Tuberculose Pulmonar/tratamento farmacológico , Adulto Jovem
6.
J Med Virol ; 90(8): 1375-1382, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29663435

RESUMO

Preemptive antiviral therapy based on detecting cytomegalovirus (CMV) DNAemia above a preestablished threshold is the mainstay strategy for the prevention of CMV disease in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients; nevertheless, CMV DNAemia, even at low levels, may increase mortality. We investigated whether surveillance of saliva for the presence of CMV DNA may anticipate the occurrence of CMV DNAemia. This was a prospective observational study with 53 consecutively enrolled allo-HSCT recipients. Saliva and plasma specimens were collected on a weekly basis from Day 0 to Day 100 after transplantation. CMV DNA was quantified in both specimen types using the Abbott Real-Time PCR assay (Abbott Molecular, Des Plaines, IL). CMV DNA was quantifiable in 44 (83%) patients: either in saliva (n = 1) or plasma (n = 12) only, or in both specimen types (n = 31). CMV oral shedding preceded the occurrence of CMV DNAemia in eight patients (18.2%), while the opposite pattern was observed in 21 patients (47.7%). The CMV DNA loads quantified in saliva and plasma correlated modestly (P = 0.33; P = 0.013) and did not differ in magnitude (P = 0.527). No transplantation factors, other than recipient CMV seropositivity, were associated with oral CMV DNA shedding; serum CMV IgG levels were comparable, regardless of the timing of the detection of CMV DNA at both sites. In summary, screening of saliva specimens for the presence of CMV DNA appear to be of limited value for anticipating the occurrence of CMV DNAemia in allo-HSCT recipients.


Assuntos
Infecções por Citomegalovirus/virologia , Citomegalovirus/isolamento & purificação , DNA Viral/análise , Saliva/virologia , Eliminação de Partículas Virais , Adulto , Infecções por Citomegalovirus/diagnóstico , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Plasma/virologia , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Transplante Homólogo/efeitos adversos , Viremia/diagnóstico , Adulto Jovem
7.
Eur J Clin Microbiol Infect Dis ; 37(12): 2331-2339, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30264355

RESUMO

The use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) for diagnosing viral infections by directly testing clinical specimens has not previously been explored. In this proof-of-principle study, we tested the hypothesis that proteomic profiling of cerebrospinal fluid (CSF) by mass spectrometry may be useful in the diagnosis of enteroviral (EV) meningitis. A total of 114 cryopreserved CSF samples were analyzed, of which 47 were positive for EV and 67 were negative. Total CSF proteins were precipitated and subjected to MALDI-TOF-MS analysis in a low (2-20 kDa) molecular weight range using a MicroFlex LT mass spectrometer. The whole data set was randomly split into a training set (n = 76 specimens) and a validation set (n = 38 samples). Backward/forward stepwise logistic regression analyses identified 30 peaks that were differentially present in EV-positive and EV-negative specimens. These were used to build a model which displayed an overall classification accuracy of 93%. The discriminative ability of the model was confirmed by using a validation sample set (overall accuracy 83%). In fact, the model was able to correctly classify 61 out of 67 EV-negative samples and 42 out of 47 EV-positive specimens. EV meningitis is associated with a distinctive protein profile that may be directly detectable in CSF specimens by MALDI-TOF-MS.


Assuntos
Infecções por Enterovirus/líquido cefalorraquidiano , Infecções por Enterovirus/diagnóstico , Meningite Viral/diagnóstico , Proteômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Adolescente , Criopreservação , Feminino , Perfilação da Expressão Gênica , Humanos , Modelos Logísticos , Masculino , Meningite Viral/líquido cefalorraquidiano , Estudo de Prova de Conceito , Adulto Jovem
8.
Transpl Infect Dis ; 20(4): e12926, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29809298

RESUMO

Risk factors (RFs) and mortality data of community-acquired respiratory virus (CARVs) lower respiratory tract disease (LRTD) with concurrent pulmonary co-infections in the setting of allogeneic hematopoietic stem cell transplantation (allo-HSCT) is scarce. From January 2011 to December 2017, we retrospectively compared the outcome of allo-HSCT recipients diagnosed of CARVs LRTD mono-infection (n = 52, group 1), to those with viral, bacterial, or fungal pulmonary CARVs LRTD co-infections (n = 15, group 2; n = 20, group 3, and n = 11, group 4, respectively), and with those having bacterial pneumonia mono-infection (n = 19, group 5). Overall survival (OS) at day 60 after bronchoalveolar lavage (BAL) was significantly higher in group 1, 2, and 4 compared to group 3 (77%, 67%, and 73% vs 35%, respectively, P = .012). Recipients of group 5 showed a trend to better OS compared to those of group 3 (62% vs 35%, P = .1). Multivariate analyses showed bacterial co-infection as a RF for mortality (hazard ratio[HR] 2.65, 95% C.I. 1.2-6.9, P = .017). We identified other 3 RFs for mortality: lymphocyte count <0.5 × 109 /L (HR 2.6, 95% 1.1-6.2, P = .026), the occurrence of and CMV DNAemia requiring antiviral therapy (CMV-DNAemia-RAT) at the time of BAL (HR 2.32, 95% C.I. 1.1-4.9, P = .03), and the need of oxygen support (HR 8.3, 95% C.I. 2.9-35.3, P = .004). CARV LRTD co-infections are frequent and may have a negative effect in the outcome, in particular in the context of bacterial co-infections.


Assuntos
Líquido da Lavagem Broncoalveolar/microbiologia , Coinfecção/mortalidade , Infecções Comunitárias Adquiridas/mortalidade , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Infecções Respiratórias/mortalidade , Adulto , Idoso , Antivirais/uso terapêutico , Bactérias/isolamento & purificação , Lavagem Broncoalveolar , Coinfecção/microbiologia , Coinfecção/terapia , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/terapia , Feminino , Fungos/isolamento & purificação , Humanos , Pulmão/microbiologia , Masculino , Pessoa de Meia-Idade , Infecções Respiratórias/microbiologia , Infecções Respiratórias/terapia , Estudos Retrospectivos , Fatores de Risco , Transplante Homólogo/efeitos adversos , Vírus/isolamento & purificação
9.
J Gen Virol ; 98(10): 2530-2542, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28874227

RESUMO

Mixed cytomegalovirus (CMV) infections are associated with delayed viral clearance in solid organ transplant recipients. We investigated whether this could be extrapolated to allogeneic stem cell transplant (allo-SCT) recipients. A total of 48 plasma specimens, obtained during 29 episodes of active CMV infection in 25 non-consecutive allo-SCT patients, were analysed. Baseline blood specimens, drawn shortly prior to the inception of pre-emptive antiviral therapy (pre-treatment specimen; n=29), as well as follow-up samples obtained either after the initiation of antiviral therapy (post-treatment specimen; n=15) or during recurrent episodes (n=4) were analysed. Plasma CMV DNA loads were quantified by real-time PCR and the CMV genotyping was performed by ultra-deep sequencing of hypervariable regions in the genes coding for glycoproteins N (gN) and O (gO). A trend towards higher CMV DNA peak loads, longer CMV DNAemia episode durations and slower CMV DNAemia decay rates was observed for episodes with mixed CMV genotype populations compared to those caused by single CMV variants, although the differences did not reach statistical significance. The length of the treatment course required to clear DNAemia was significantly longer in these mixed episodes (P=0.002). Significant changes in the number or frequency of CMV gN or gO genetic variants were documented following the initiation of antiviral therapy or in recurrent episodes. CMV diversity may have a major impact on the kinetics of CMV DNAemia clearance during the treatment of active CMV infection episodes in allo-SCT recipients.


Assuntos
Infecções por Citomegalovirus/tratamento farmacológico , Citomegalovirus/genética , DNA Viral/sangue , Transplante de Células-Tronco/efeitos adversos , Transplante Homólogo/efeitos adversos , Adulto , Idoso , Antivirais/uso terapêutico , Sequência de Bases , Citomegalovirus/classificação , Citomegalovirus/efeitos dos fármacos , Infecções por Citomegalovirus/virologia , Feminino , Variação Genética/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA , Carga Viral
10.
J Gen Virol ; 98(7): 1855-1863, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28691896

RESUMO

The level of antioxidants, such as thiol-containing tripeptide glutathione (GSH), in cytomegalovirus (CMV)-infected cells is notably increased. We previously showed that GSH levels in plasma, as measured by untargeted 1H nuclear magnetic resonance, are higher in allogeneic stem cell transplant (allo-SCT) recipients who subsequently develop CMV viraemia. We hypothesized that the net level of oxidative-stress markers present in plasma may be reduced in patients who develop CMV DNAaemia compared to those who do not. We serially monitored the levels of malondialdehyde (MDA) and carbonylated proteins (CPs) early after allo-SCT and assessed whether they could predict the occurrence of CMV DNAaemia. MDA levels were measured in 43 patients (28 had CMV DNAaemia) and CPs were quantified in 53 patients (38 patients developed CMV DNAaemia). The area under the curve (AUC) value for MDA, but not for CPs, was significantly lower in patients who subsequently developed CMV DNAaemia compared to those who remained DNAaemia-free (P=0.043). A trend toward lower MDA AUC values was observed in episodes of CMV DNAaemia with faster CMV replicative kinetics and in those who reached higher peak CMV DNA levels. Moreover, receiver operating characteristic curve analyses indicated that the MDA biomarker had the predictive ability to discriminate between patients with or without subsequent CMV DNAaemia (AUC=0.69, 95 % confidence interval 0.51-0.85, P=0.05). In summary, serial quantitation of MDA may be useful for individualizing antiviral prophylaxis therapies (targeted prophylaxis) in the upcoming era of new antiviral drugs with improved safety profiles.


Assuntos
Citomegalovirus/genética , DNA Viral/sangue , Glutationa/sangue , Malondialdeído/sangue , Carbonilação Proteica/fisiologia , Transplante de Células-Tronco/efeitos adversos , Carga Viral/métodos , Viremia/diagnóstico , Adulto , Idoso , Antioxidantes/metabolismo , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/virologia , Feminino , Neoplasias Hematológicas/patologia , Neoplasias Hematológicas/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Curva ROC , Viremia/virologia
11.
Transpl Infect Dis ; 19(4)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28471073

RESUMO

BACKGROUND: We conducted a retrospective single-center study to investigate the potential impact of cytomegalovirus (CMV) DNAemia on mortality in allogeneic stem cell transplant (allo-SCT) recipients. METHODS: A total of 151 consecutive patients who underwent T-cell replete allo-SCT were included in the study. Patients with CMV DNAemia were treated preemptively with antivirals upon detection of plasma CMV DNA loads >1500 IU/mL. RESULTS: At least one episode of CMV DNAemia occurred in 109 (72.2%) patients, and 67 of these patients (61.5%) required one or more courses of antiviral therapy. The cumulative incidence of 1-year overall and non-relapse mortality (NRM) was 28.5% (95% confidence interval [CI], 18.4%-39.5%) and 23.2% (95% CI 12.81%-35.4%), respectively. The occurrence of either CMV DNAemia or CMV recurrences had no apparent effect on 1-year overall mortality and NRM; nevertheless, a trend towards an increased risk of death was seen in patients with one or more episodes of CMV DNAemia requiring antiviral therapy (hazard ratio [HR], 2.10; 95% CI, 0.96-4.61; P=.06 for overall mortality, and HR, 2.36; 95% CI, 0.96-5.76; P=.06 for NRM) but not in those displaying one or more self-resolving episodes. CONCLUSION: Therefore, the data suggest that withholding preemptive antiviral therapy until the plasma CMV DNA load reaches 1500 IU/mL has no apparent detrimental effect on patient survival.


Assuntos
Antivirais/uso terapêutico , Infecções por Citomegalovirus/mortalidade , Citomegalovirus/isolamento & purificação , DNA Viral/sangue , Transplante de Células-Tronco/mortalidade , Adolescente , Adulto , Idoso , Citomegalovirus/genética , Infecções por Citomegalovirus/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Espanha , Transplante de Células-Tronco/efeitos adversos , Transplantados , Transplante Homólogo , Adulto Jovem
12.
Transpl Int ; 29(11): 1196-1204, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27529151

RESUMO

Pathogenic interactions between bacteria and cytomegalovirus (CMV) may potentially occur early after allogeneic stem cell transplantation (allo-SCT). This possibility nevertheless has not been investigated in depth. This was a retrospective study that included 170 consecutive patients who underwent 173 allo-SCTs. Both bacterial infection (most of which were bacteremic) and CMV DNAemia were detected in 78 allo-SCTs (62.9%). In total, 51 and 32 episodes of bacterial infection preceded or occurred after CMV DNAemia detection, respectively. Both events were diagnosed concurrently in four allo-SCTs. The cumulative incidence of bacterial infection (of any type) over the study period was comparable in patients with or without a preceding episode of CMV DNAemia (P = 0.321). Cox proportional hazards regression analysis failed to identify CMV DNAemia as a significant risk factor for bacterial infection. Likewise, the cumulative incidence of CMV DNAemia within the study period was not significantly different in patients with or without a preceding episode of bacterial infection (P = 0.189). Furthermore, the occurrence of bacterial infection within episodes of active CMV infection had no apparent impact on the kinetics of CMV DNAemia. Our data, thus, do not support the existence of a bidirectional synergistic effect between bacterial infection and active CMV infection in the allo-SCT setting.


Assuntos
Infecções Bacterianas/complicações , Infecções por Citomegalovirus/complicações , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Adolescente , Adulto , Idoso , Bacteriemia/complicações , Citomegalovirus , DNA Viral/sangue , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Transplante Homólogo/efeitos adversos , Adulto Jovem
17.
Antibiotics (Basel) ; 10(5)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065605

RESUMO

Infections caused by multidrug-resistant Acinetobacter baumannii would benefit from the development of novel treatment approaches. Compounds that interfere with bacterial iron metabolism, such as iron chelators and gallium nitrate, have previously been shown to have antimicrobial activity against A. baumannii. In this study, we characterize the effect of LpxC inhibitors on the antimicrobial activity of previously characterized iron chelators, 2,2'-bipyridyl (BIP) and deferiprone (DFP), and gallium nitrate (Ga(NO3)3) against A. baumannii reference strains and multidrug-resistant clinical isolates. The LpxC inhibitor LpxC-2 was synergistic with BIP for 30% of strains tested (FICI values: 0.38-1.02), whereas inhibition with LpxC-4 was synergistic with BIP for 60% of strains tested (FICI values: 0.09-0.75). In time-kill assays, combinations of BIP with both LpxC inhibitors demonstrated synergistic activity, with a more than 3 log10 reduction in bacterial counts compared to BIP alone. LpxC-2 was synergistic with Ga(NO3)3 for 50% of strains tested (FICI values: 0.27-1.0), whereas LpxC-4 was synergistic with Ga(NO3)3 for all strains tested (FICI values: 0.08-≤0.50). In time-kill assays, combinations of Ga(NO3)3 with LpxC-2 and LpxC-4 decreased the growth of both strains compared to each compound separately; however, only the combination with LpxC-4 met the defined criteria for synergy. These results identify a novel synergy between two antimicrobial classes against A. baumannii strains.

18.
Enferm Infecc Microbiol Clin (Engl Ed) ; 38(5): 206-211, 2020 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31668859

RESUMO

INTRODUCTION: The sensitivities of conventional mycobacterial culture in solid or liquid media and acid-fast bacilli (AFB) smear microscopy for Mycobacterium tuberculosis complex (MTBC) detection in extrapulmonary specimens are suboptimal. We evaluated the field performance of the Abbott RealTime MTB assay for the diagnosis of extrapulmonary tuberculosis in a low-prevalence setting. METHODS: The total number of extrapulmonary specimens with mycobacterial culture and PCR results was 566: sterile fluids (n=278), non-sterile fluids (n=147), lymph node material (n=69) tissue biopsies (n=63), and abscess aspirates (n=9). A composite standard consisting of mycobacterial culture results, clinical treatment response to anti-TB drugs, when administered, and histopathology, radiological and laboratory findings were used as a reference for sensitivity and specificity calculations. RESULTS: Mycobacterial cultures and PCR were positive in 17 and 28 specimens, respectively. The overall agreement between culture and PCR was moderate (Cohen's kappa coefficient: 0.549; P=0.0001). Taking as a reference our composite standard, the sensitivity of the Abbott PCR assay was 77.7%, the specificity 99.5%, the PPV 95.4%, and the NPV 98.8%. In turn, the sensitivity of the mycobacterial culture was 62.9%, the specificity and PPV 100%, and the NPV 97.9%. CONCLUSION: The good field performance of the Abbott RealTime MTB assay makes it valuable for the diagnosis of extrapulmonary tuberculosis in a low-prevalence setting. The use of molecular methods along with culture improves the diagnosis of extrapulmonary tuberculosis.


Assuntos
Técnicas Bacteriológicas/métodos , Mycobacterium tuberculosis , Tuberculose , Humanos , Mycobacterium tuberculosis/isolamento & purificação , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Tuberculose/diagnóstico
19.
Diagn Microbiol Infect Dis ; 94(1): 22-27, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30579656

RESUMO

We assessed the impact of several parameters, including the nature of the episode of Cytomegalovirus (CMV) DNAemia, the use of preemptive antiviral therapy, and the blood cell content in CMV DNA loads measured in whole blood (WB) and plasma (PL). CMV DNA load was quantified in 245 paired specimens collected within 43 postengraftment episodes of CMV DNAemia by using the CMV RealTime CMV PCR (Abbott Molecular). Concordant categorical results were obtained for 78.4% of paired specimens (Kappa index, 0.385; P = <0.001). Overall, CMV DNA loads in PL were higher than those in WB (mean bias, +0.115 log IU/mL) in both initial and recurrent episodes; this was so in post-antiviral treatment but not in pretreatment paired specimens. Median CMV DNA doubling time values in both compartments were not significantly different. Leukocyte counts had a significant impact on the comparability of CMV DNA loads measured in both matrices.


Assuntos
Sangue/virologia , Infecções por Citomegalovirus/virologia , Citomegalovirus/isolamento & purificação , DNA Viral/análise , Transplantados , Carga Viral/métodos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Transplante Homólogo/efeitos adversos
20.
J Infect ; 78(5): 393-401, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30797790

RESUMO

OBJECTIVES: To date no definitive cut-off value for cytomegalovirus (CMV) DNA load in bronchoalveolar lavage (BAL) fluid specimens has been established to discriminate between CMV pneumonia and pulmonary CMV DNA shedding in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients. METHODS: The current retrospective study is aimed at assessing the range of CMV DNA loads quantified in BAL fluid specimens from allo-HSCT patients with pneumonia in which different microorganisms were causally involved. RESULTS: A total of 144 BAL specimens from 123 patients were included. CMV DNA was detected in 56 out of 144 BAL fluid specimens and the median CMV DNA load from patients in whom CMV pneumonia was unlikely or could be tentatively ruled out was 1210 (31-68, 920) IU/ml. The frequency of CMV DNA detection and median CMV DNA loads were comparable, irrespective of the attributable cause of pneumonia. Detection of CMV DNA loads in BAL fluid specimens >500 IU/ml was independently associated with pneumonia-attributable mortality. CONCLUSIONS: The current study highlights the difficulty in establishing universal CMV DNA load thresholds in BAL fluid specimens for distinguishing between CMV pneumonia and pulmonary CMV DNA shedding, and suggests that the presence of CMV DNA in BAL fluid specimens beyond a certain level may have a deleterious impact on patient outcome.


Assuntos
Líquido da Lavagem Broncoalveolar/virologia , Infecções por Citomegalovirus/diagnóstico , Citomegalovirus/isolamento & purificação , DNA Viral/isolamento & purificação , Pneumonia Viral/diagnóstico , Transplantados , Eliminação de Partículas Virais , Adulto , Idoso , Idoso de 80 Anos ou mais , Citomegalovirus/genética , Infecções por Citomegalovirus/virologia , DNA Viral/genética , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/virologia , Estudos Retrospectivos , Transplante Homólogo , Carga Viral
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