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1.
J Med Virol ; 94(1): 99-109, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34570905

RESUMO

A severe pandemic of Coronavirus Disease (COVID-19) has been sweeping the globe since 2019, and this time, it did not stop, with frequent mutations transforming into virulent strains, for instance, B.1.1.7, B.1.351, and B.1.427. In recent months, a fungal infection, mucormycosis has emerged with more fatal responses and significantly increased mortality rate. To measure the severity and potential alternative approaches against black fungus coinfection in COVID-19 patients, PubMed, Google Scholar, World Health Organization (WHO) newsletters, and other online resources, based on the cases reported and retrospective observational analysis were searched from the years 2015-2021. The studies reporting mucormycosis with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) coinfection and/or demonstrating potential risk factors, such as a history of diabetes mellitus or suppressed immune system were included, and reports published in non-English language were excluded. More than 20 case reports and observational studies on black fungus coinfection in COVID-19 patients were eligible for inclusion. The results indicated that diabetes mellitus, hyperglycemic, and immunocompromised COVID-19 patients with mucormycosis were at a higher risk. We found that it was prudent to assess the potential risk factors and severity of invasive mycosis via standardized diagnostic and clinical settings. Large-scale studies need to be conducted to identify early biomarkers and optimization of diagnostic methods has to be established per population and geographical variation. This will not only help clinicians around the world to detect the coinfection in time but also will prepare them for future outbreaks of other potential pandemics.


Assuntos
COVID-19/epidemiologia , Coinfecção/epidemiologia , Mucormicose/epidemiologia , Mucormicose/mortalidade , SARS-CoV-2/isolamento & purificação , Diabetes Mellitus/patologia , Humanos , Hiperglicemia/patologia , Hospedeiro Imunocomprometido/fisiologia , Mucorales/crescimento & desenvolvimento , Mucorales/isolamento & purificação , Mucormicose/patologia , Estudos Retrospectivos , Fatores de Risco
2.
J Hepatol ; 75(5): 1128-1141, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34171432

RESUMO

BACKGROUND & AIMS: Our previous genomic whole-exome sequencing (WES) data identified the key ErbB pathway mutations that play an essential role in regulating the malignancy of gallbladder cancer (GBC). Herein, we tested the hypothesis that individual cellular components of the tumor microenvironment (TME) in GBC function differentially to participate in ErbB pathway mutation-dependent tumor progression. METHODS: We engaged single-cell RNA-sequencing to reveal transcriptomic heterogeneity and intercellular crosstalk from 13 human GBCs and adjacent normal tissues. In addition, we performed WES analysis to reveal the genomic variations related to tumor malignancy. A variety of bulk RNA-sequencing, immunohistochemical staining, immunofluorescence staining and functional experiments were employed to study the difference between tissues with or without ErbB pathway mutations. RESULTS: We identified 16 cell types from a total of 114,927 cells, in which epithelial cells, M2 macrophages, and regulatory T cells were predominant in tumors with ErbB pathway mutations. Furthermore, epithelial cell subtype 1, 2 and 3 were mainly found in adenocarcinoma and subtype 4 was present in adenosquamous carcinoma. The tumors with ErbB pathway mutations harbored larger populations of epithelial cell subtype 1 and 2, and expressed higher levels of secreted midkine (MDK) than tumors without ErbB pathway mutations. Increased MDK resulted in an interaction with its receptor LRP1, which is expressed by tumor-infiltrating macrophages, and promoted immunosuppressive macrophage differentiation. Moreover, the crosstalk between macrophage-secreted CXCL10 and its receptor CXCR3 on regulatory T cells was induced in GBC with ErbB pathway mutations. Elevated MDK was correlated with poor overall survival in patients with GBC. CONCLUSIONS: This study has provided valuable insights into transcriptomic heterogeneity and the global cellular network in the TME, which coordinately functions to promote the progression of GBC with ErbB pathway mutations; thus, unveiling novel cellular and molecular targets for cancer therapy. LAY SUMMARY: We employed single-cell RNA-sequencing and functional assays to uncover the transcriptomic heterogeneity and intercellular crosstalk present in gallbladder cancer. We found that ErbB pathway mutations reduced anti-cancer immunity and led to cancer development. ErbB pathway mutations resulted in immunosuppressive macrophage differentiation and regulatory T cell activation, explaining the reduced anti-cancer immunity and worse overall survival observed in patients with these mutations.


Assuntos
Receptores ErbB/imunologia , Neoplasias da Vesícula Biliar/imunologia , Hospedeiro Imunocomprometido/fisiologia , Midkina/efeitos adversos , Proliferação de Células/genética , China/epidemiologia , Receptores ErbB/antagonistas & inibidores , Neoplasias da Vesícula Biliar/epidemiologia , Neoplasias da Vesícula Biliar/fisiopatologia , Humanos , Midkina/genética , Análise de Sequência de RNA/métodos , Análise de Sequência de RNA/estatística & dados numéricos , Transdução de Sinais/genética , Análise de Célula Única/métodos , Análise de Célula Única/estatística & dados numéricos , Sequenciamento do Exoma/métodos , Sequenciamento do Exoma/estatística & dados numéricos
3.
Ann Hematol ; 100(1): 1-10, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33009935

RESUMO

Progressive multifocal leukoencephalopathy (PML) is a rare opportunistic infection with high mortality rate usually seen in the context of immunosuppression. Although cases have been reported largely in patients with HIV/AIDS, following the use of monoclonal antibodies and occasionally in haematological malignancies, there is no review to date of patients with smouldering or treated myeloma who developed PML. Here, we conducted a literature search of PML cases in patients with multiple myeloma (MM), analyse patient and disease characteristics and describe the possible mechanisms that could lead to the development of PML. The lack of data and case reports until 2010 may indicate that PML in MM is underdiagnosed. Simultaneously, with an expanding field of new therapeutic options, patients with MM live longer, albeit continually immunosuppressed, and at risk of opportunistic infections. Emerging new treatments for PML in the horizon render the need to look out for this complication mandatory, and more case reports are needed to enrich our knowledge in this field.


Assuntos
Hospedeiro Imunocomprometido/efeitos dos fármacos , Leucoencefalopatia Multifocal Progressiva/tratamento farmacológico , Leucoencefalopatia Multifocal Progressiva/imunologia , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/imunologia , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Humanos , Hospedeiro Imunocomprometido/fisiologia , Fatores Imunológicos/metabolismo , Fatores Imunológicos/farmacologia , Fatores Imunológicos/uso terapêutico , Leucoencefalopatia Multifocal Progressiva/metabolismo , Mieloma Múltiplo/metabolismo
4.
AIDS Res Ther ; 18(1): 28, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33952300

RESUMO

Coronavirus disease 2019 (COVID-19) was first detected in December 2019. In March 2020, the World Health Organization declared COVID-19 a pandemic. People with underlying medical conditions may be at greater risk of infection and experience complications from COVID-19. COVID-19 has the potential to affect People living with HIV (PLWH) in various ways, including be increased risk of COVID-19 acquisition and interruptions of HIV treatment and care. The purpose of this review article is to evaluate the impact of COVID-19 among PLWH. The contents focus on 4 topics: (1) the pathophysiology and host immune response of people infected with both SARS-CoV-2 and HIV, (2) present the clinical manifestations and treatment outcomes of persons with co-infection, (3) assess the impact of antiretroviral HIV drugs among PLWH infected with COVID-19 and (4) evaluate the impact of the COVID-19 pandemic on HIV services.


Assuntos
Antirretrovirais/uso terapêutico , COVID-19/patologia , Coinfecção/patologia , Infecções por HIV/patologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/imunologia , Adulto , COVID-19/complicações , COVID-19/imunologia , Coinfecção/imunologia , Citocinas/sangue , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , HIV-1/imunologia , Humanos , Hospedeiro Imunocomprometido/imunologia , Hospedeiro Imunocomprometido/fisiologia , Linfopenia/patologia , Pessoa de Meia-Idade , Resultado do Tratamento , Tratamento Farmacológico da COVID-19
5.
Int J Mol Sci ; 22(7)2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33807229

RESUMO

Cytomegalovirus (CMV) causes clinical issues primarily in immune-suppressed conditions. CMV-associated anterior uveitis (CMV-AU) is a notable new disease entity manifesting recurrent ocular inflammation in immunocompetent individuals. As patient demographics indicated contributions from genetic background and immunosenescence as possible underlying pathological mechanisms, we analyzed the immunogenetics of the cohort in conjunction with cell phenotypes to identify molecular signatures of CMV-AU. Among the immune cell types, natural killer (NK) cells are main responders against CMV. Therefore, we first characterized variants of polymorphic genes that encode differences in CMV-related human NK cell responses (Killer cell Immunoglobulin-like Receptors (KIR) and HLA class I) in 122 CMV-AU patients. The cases were then stratified according to their genetic features and NK cells were analyzed for human CMV-related markers (CD57, KLRG1, NKG2C) by flow cytometry. KIR3DL1 and HLA class I combinations encoding strong receptor-ligand interactions were present at substantially higher frequencies in CMV-AU. In these cases, NK cell profiling revealed expansion of the subset co-expressing CD57 and KLRG1, and together with KIR3DL1 and the CMV-recognizing NKG2C receptor. The findings imply that a mechanism of CMV-AU pathogenesis likely involves CMV-responding NK cells co-expressing CD57/KLRG1/NKG2C that develop on a genetic background of KIR3DL1/HLA-B allotypes encoding strong receptor-ligand interactions.


Assuntos
Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Uveíte Anterior/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD57/genética , Antígenos CD57/imunologia , Estudos de Coortes , Citomegalovirus/imunologia , Citomegalovirus/patogenicidade , Infecções por Citomegalovirus/imunologia , Feminino , Genes MHC Classe I/genética , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Hospedeiro Imunocomprometido/imunologia , Hospedeiro Imunocomprometido/fisiologia , Células Matadoras Naturais/fisiologia , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Masculino , Pessoa de Meia-Idade , Subfamília C de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília C de Receptores Semelhantes a Lectina de Células NK/imunologia , Subfamília C de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Receptores KIR/genética , Transplante Homólogo/efeitos adversos , Uveíte Anterior/genética , Uveíte Anterior/virologia
6.
Crit Care Med ; 48(9): e768-e775, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32706556

RESUMO

OBJECTIVES: To assess the response to initial oxygenation strategy according to clinical variables available at admission. DESIGN: Multicenter cohort study. SETTING: Thirty French and Belgium medical ICU. SUBJECTS: Immunocompromised patients with hypoxemic acute respiratory failure. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Data were extracted from the Groupe de Recherche en Reanimation Respiratoire du patient d'Onco-Hématologie database. Need for invasive mechanical ventilation was the primary endpoint. Secondary endpoint was day-28 mortality. Six-hundred forty-nine patients were included. First oxygenation strategies included standard oxygen (n = 245, 38%), noninvasive ventilation (n = 285; 44%), high-flow nasal cannula oxygen (n = 55; 8%), and noninvasive ventilation + high-flow nasal cannula oxygen (n = 64; 10%). Bilateral alveolar pattern (odds ratio = 1.67 [1.03-2.69]; p = 0.04), bacterial (odds ratio = 1.98 [1.07-3.65]; p = 0.03) or opportunistic infection (odds ratio = 4.75 [2.23-10.1]; p < 0.001), noninvasive ventilation use (odds ratio = 2.85 [1.73-4.70]; p < 0.001), Sequential Organ Failure Assessment score (odds ratio = 1.19 [1.10-1.28]; p < 0.001), and ratio of PaO2 and FIO2 less than 100 at ICU admission (odds ratio = 1.96 [1.27-3.02]; p = 0.0002) were independently associated with intubation rate. Day-28 mortality was independently associated with bacterial (odds ratio = 2.34 [1.10-4.97]; p = 0.03) or opportunistic infection (odds ratio = 4.96 [2.11-11.6]; p < 0.001), noninvasive ventilation use (odds ratio = 2.35 [1.35-4.09]; p = 0.003), Sequential Organ Failure Assessment score (odds ratio = 1.19 [1.10-1.28]; p < 0.001), and ratio of PaO2 and FIO2 less than 100 at ICU admission (odds ratio = 1.97 [1.26-3.09]; p = 0.003). High-flow nasal cannula oxygen use was neither associated with intubation nor mortality rates. CONCLUSIONS: Some clinical characteristics at ICU admission including etiology and severity of acute respiratory failure enable to identify patients at high risk for intubation.


Assuntos
Estado Terminal/terapia , Hospedeiro Imunocomprometido/fisiologia , Intubação Intratraqueal/estatística & dados numéricos , Oxigenoterapia/métodos , Insuficiência Respiratória/terapia , Infecção Hospitalar/epidemiologia , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Tempo de Internação , Pulmão/patologia , Escores de Disfunção Orgânica , Insuficiência Respiratória/epidemiologia , Insuficiência Respiratória/mortalidade , Índice de Gravidade de Doença
7.
Crit Care Med ; 48(10): e916-e926, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32931197

RESUMO

OBJECTIVES: To describe the Children's Hospital Association's Improving Pediatric Sepsis Outcomes sepsis definitions and the identified patients; evaluate the definition using a published framework for evaluating sepsis definitions. DESIGN: Observational cohort. SETTING: Multicenter quality improvement collaborative of 46 hospitals from January 2017 to December 2018, excluding neonatal ICUs. PATIENTS: Improving Pediatric Sepsis Outcomes Sepsis was defined by electronic health record evidence of suspected infection and sepsis treatment or organ dysfunction. A more severely ill subgroup, Improving Pediatric Sepsis Outcomes Critical Sepsis, was defined, approximating septic shock. INTERVENTIONS: Participating hospitals identified patients, extracted data, and transferred de-identified data to a central data warehouse. The definitions were evaluated across domains of reliability, content validity, construct validity, criterion validity, measurement burden, and timeliness. MEASUREMENTS AND MAIN RESULTS: Forty hospitals met data quality criteria across four electronic health record platforms. There were 23,976 cases of Improving Pediatric Sepsis Outcomes Sepsis, including 8,565 with Improving Pediatric Sepsis Outcomes Critical Sepsis. The median age was 5.9 years. There were 10,316 (43.0%) immunosuppressed or immunocompromised patients, 4,135 (20.3%) with central lines, and 2,352 (11.6%) chronically ventilated. Among Improving Pediatric Sepsis Outcomes Sepsis patients, 60.8% were admitted to intensive care, 26.4% had new positive-pressure ventilation, and 19.7% received vasopressors. Median hospital length of stay was 6.0 days (3.0-13.0 d). All-cause 30-day in-hospital mortality was 958 (4.0%) in Improving Pediatric Sepsis Outcomes Sepsis; 541 (6.3%) in Improving Pediatric Sepsis Outcomes Critical Sepsis. The Improving Pediatric Sepsis Outcomes Sepsis definitions demonstrated strengths in content validity, convergent construct validity, and criterion validity; weakness in reliability. Improving Pediatric Sepsis Outcomes Sepsis definitions had significant initial measurement burden (median time from case completion to submission: 15 mo [interquartile range, 13-18 mo]); timeliness improved once data capture was established (median, 26 d; interquartile range, 23-56 d). CONCLUSIONS: The Improving Pediatric Sepsis Outcomes Sepsis definitions demonstrated feasibility for large-scale data abstraction. The patients identified provide important information about children treated for sepsis. When operationalized, these definitions enabled multicenter identification and data aggregation, indicating practical utility for quality improvement.


Assuntos
Registros Eletrônicos de Saúde/estatística & dados numéricos , Hospitais Pediátricos/estatística & dados numéricos , Unidades de Terapia Intensiva Pediátrica/estatística & dados numéricos , Melhoria de Qualidade/organização & administração , Sepse/terapia , Adolescente , Criança , Pré-Escolar , Feminino , Mortalidade Hospitalar/tendências , Humanos , Hospedeiro Imunocomprometido/fisiologia , Lactente , Tempo de Internação/estatística & dados numéricos , Masculino , Escores de Disfunção Orgânica , Respiração com Pressão Positiva , Reprodutibilidade dos Testes , Sepse/mortalidade , Índice de Gravidade de Doença , Choque Séptico/mortalidade , Choque Séptico/terapia
8.
Am J Emerg Med ; 38(6): 1298.e1-1298.e3, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32081551

RESUMO

Bacterial meningitis is a life-threatening condition that should be addressed as an emergency. The typical culprit microorganisms are targeted empirically with ceftriaxone and vancomycin, in the absence of an immunocompromised state. In this case report, however, we are describing a case of meningitis secondary to Weissella confusa, bacteria inherently resistant to the two drugs commonly used to empirically treat meningitis. Weissella spp. are Gram-positive, catalase-negative coccobacilli and an infrequent cause of infection in humans. Bacteremia followed by endocarditis are the typical clinical manifestations of W. confusa in humans. Other reported manifestations include post-operative osteomyelitis, thumb abscess, infected prosthetic joint, infected peritoneal fluid and peritonitis. To our knowledge, this is the first case of meningitis due to Weissella confusa in the literature. Therefore, we conclude that the isolation of Gram-positive coccobacilli resistant to vancomycin, especially in an immunocompromised host, should raise the suspicion of W. confusa.


Assuntos
Meningites Bacterianas/microbiologia , Idoso , Antibacterianos/uso terapêutico , Febre/etiologia , Humanos , Hospedeiro Imunocomprometido/efeitos dos fármacos , Hospedeiro Imunocomprometido/fisiologia , Masculino , Meningites Bacterianas/tratamento farmacológico , Testes de Sensibilidade Microbiana/métodos , Punção Espinal/métodos , Weissella/efeitos dos fármacos , Weissella/isolamento & purificação , Weissella/patogenicidade
9.
Clin Neuropathol ; 37(1): 22-27, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29035192

RESUMO

Bacillus cereus is a widely-distributed, gram-positive or variable, rod-shaped bacterium frequently considered a contaminant in clinical specimens. It is recognized as a potential pathogen inducing self-limiting emetic or diarrheal food poisoning or localized infection in immunocompetent patients. True B. cereus bacteremia is uncommon and mainly observed in fragile patients, notably in immunocompromised individuals. We report clinical, radiological, and pathological findings of a 64-year-old patient with a history of acute myeloid leukemia who initially presented a fever while neutropenic after the induction of a second cycle of chemotherapy. He developed B. cereus bacteremia with invasive infection and a fatal outcome. The clinical and radiological data of this case are compared to a previously-published series of 21 patients from our institution with B. cereus bacteremia. This study highlights the clinical challenge to diagnose B. cereus and the importance of the delay between the detection of B. cereus and the initiation of an effective targeted antibiotic therapy. This case presented an aggressive evolution with multiple necrotic and hemorrhagic foci in the brain. Upon histological examination, B. cereus virulence was notably reflected by the dissection of blood vessel walls by the bacilli and luminal occlusion, a pattern that has not been yet reported.
.


Assuntos
Bacillus cereus/citologia , Bacteriemia/patologia , Encéfalo/patologia , Doenças do Sistema Nervoso/patologia , Bacteriemia/diagnóstico , Humanos , Hospedeiro Imunocomprometido/fisiologia , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/diagnóstico , Neuropatologia/métodos
10.
J Emerg Med ; 54(6): 871-875, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29523423

RESUMO

BACKGROUND: Capnocytophaga canimorsus is a bacterium of the normal oral flora of dogs and cats. Human infection is caused by animal bite but is rarely observed, mainly in immunocompromised patients. We present 2 cases of C. canimorsus infection that occurred in immunocompetent patients and caused multiorgan failure and in both cases severe neurologic involvement. CASE REPORT: In the first case, we present a 69-year-old immunocompetent woman with septic shock derived from skin and soft tissue infection after a dog's bite. She developed ischemic necrosis evolving to gangrene of both forefeet and hands, infective aortic endocarditis, and neurologic involvement caused by large hemispheric hypodense lesions compatible with ischemic septical lesions. In the second case, we present a 65-year-old immunocompetent man with meningitis after a dog's bite. Despite antibiotic therapy, he developed neurologic clinical deterioration, with right sensitive hemisyndrome associated with lack of strength and motor skills of the right hand. Radiologic findings were consistent with the diagnosis of cerebritis. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Clinicians should always be aware of this pathogen, both in immunocompromised and immunocompetent patients, and consider prophylactic antibiotics after exposure.


Assuntos
Capnocytophaga/patogenicidade , Necrose/etiologia , Idoso , Animais , Antibacterianos/uso terapêutico , Mordeduras e Picadas/complicações , Cães , Serviço Hospitalar de Emergência/organização & administração , Humanos , Hospedeiro Imunocomprometido/fisiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Necrose/complicações , Radiografia/métodos
11.
J Virol ; 90(22): 10102-10112, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27581982

RESUMO

Several arenaviruses, chiefly Lassa virus (LASV), cause hemorrhagic fever disease in humans and pose serious public health concerns in their regions of endemicity. Moreover, mounting evidence indicates that the worldwide-distributed prototypic arenavirus, lymphocytic choriomeningitis virus (LCMV), is a neglected human pathogen of clinical significance. We have documented that a recombinant LCMV containing the glycoprotein (GPC) gene of LASV within the backbone of the immunosuppressive clone 13 (Cl-13) variant of the Armstrong strain of LCMV (rCl-13/LASV-GPC) exhibited Cl-13-like growth properties in cultured cells, but in contrast to Cl-13, rCl-13/LASV-GPC was unable to establish persistence in immunocompetent adult mice, which prevented its use for some in vivo experiments. Recently, V459K and K461G mutations within the GP2 cytoplasmic domain (CD) of rCl-13/LASV-GPC were shown to increase rCl-13/LASV-GPC infectivity in mice. Here, we generated rCl-13(GPC/VGKS) by introducing the corresponding revertant mutations K465V and G467K within GP2 of rCl-13 and we show that rCl-13(GPC/VGKS) was unable to persist in mice. K465V and G467K mutations did not affect GPC processing, virus RNA replication, or gene expression. In addition, rCl-13(GPC/VGKS) grew to high titers in cultured cell lines and in immunodeficient mice. Further analysis revealed that rCl-13(GPC/VGKS) infected fewer splenic plasmacytoid dendritic cells than rCl-13, yet the two viruses induced similar type I interferon responses in mice. Our findings have identified novel viral determinants of Cl-13 persistence and also revealed that virus GPC-host interactions yet to be elucidated critically contribute to Cl-13 persistence. IMPORTANCE: The prototypic arenavirus, lymphocytic choriomeningitis virus (LCMV), provides investigators with a superb experimental model system to investigate virus-host interactions. The Armstrong strain (ARM) of LCMV causes an acute infection, whereas its derivative, clone 13 (Cl-13), causes a persistent infection. Mutations F260L and K1079Q within GP1 and L polymerase, respectively, have been shown to play critical roles in Cl-13's ability to persist in mice. However, there is an overall lack of knowledge about other viral determinants required for Cl-13's persistence. Here, we report that mutations K465V and G467K within the cytoplasmic domain of Cl-13 GP2 resulted in a virus, rCl-13(GPC/VGKS), that failed to persist in mice despite exhibiting Cl-13 wild-type-like fitness in cultured cells and immunocompromised mice. This finding has uncovered novel viral determinants of viral persistence, and a detailed characterization of rCl-13(GPC/VGKS) can provide novel insights into the mechanisms underlying persistent viral infection.


Assuntos
Glicoproteínas/genética , Vírus da Coriomeningite Linfocítica/genética , Vírus da Coriomeningite Linfocítica/patogenicidade , Células A549 , Animais , Linhagem Celular , Linhagem Celular Tumoral , Chlorocebus aethiops , Citoplasma , Células Dendríticas/metabolismo , Células Dendríticas/virologia , Células HEK293 , Interações Hospedeiro-Patógeno/genética , Humanos , Hospedeiro Imunocomprometido/fisiologia , Interferon Tipo I/metabolismo , Vírus Lassa/genética , Vírus Lassa/patogenicidade , Coriomeningite Linfocítica/metabolismo , Coriomeningite Linfocítica/virologia , Camundongos , Mutação/genética , Células Vero , Replicação Viral/genética
12.
Semin Respir Crit Care Med ; 38(3): 245-252, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28578549

RESUMO

Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) remain two of the most commonly diagnosed nosocomial infections. Both are responsible for significant morbidity and mortality in hospitalized patients. The development of HAP and VAP is related to bacterial colonization of the oropharynx (and endotracheal tube in VAP) with subsequent microaspiration and development of clinical infection. Diagnosis is made based on the clinical presentation and can be confirmed by obtaining either noninvasive or invasive microbiology culture specimens. Decisions addressing initiation of antimicrobial therapy can be divided into clinical and bacteriological strategies. These strategies differ in the criteria used to determine the timing of empiric therapy, with the clinical strategy basing the decision on radiographic evidence of infection plus clinical signs and symptoms and the bacteriological strategy requiring growth of pathogens above a certain threshold from invasively obtained culture specimens. Despite the delineated pathways, these decisions remain multifactorial and should also include consideration of patient-related factors, such as immunocompetence, the risk of multidrug-resistant infection, and overall clinical condition. Patients with risk factors or signs of clinical decompensation should have empiric therapy initiated at a lower threshold. However, when possible, therapy should be directed at a confirmed infection following a positive culture result. Decisions regarding specific empiric regimens should be based on the local prevalence of infectious microorganisms along with their associated antimicrobial susceptibilities. Patients deemed at risk of infection with multidrug-resistant pathogens merit broader spectrum therapy, and immunosuppressed patients should have consideration of antifungal coverage.


Assuntos
Antibacterianos/uso terapêutico , Pneumonia Associada à Ventilação Mecânica/tratamento farmacológico , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla , Humanos , Hospedeiro Imunocomprometido/fisiologia , Pneumonia/tratamento farmacológico , Pneumonia/microbiologia , Pneumonia Associada à Ventilação Mecânica/microbiologia , Guias de Prática Clínica como Assunto , Prevalência , Radiografia Torácica , Fatores de Tempo
13.
Intern Med J ; 47(11): 1263-1269, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28516725

RESUMO

BACKGROUND: Immunosuppressed inflammatory bowel disease (IBD) patients have an increased risk of herpes zoster virus (HZV) infection. The existing live-attenuated HZV vaccine is contraindicated in some of these patients and can only be used with caution in others. AIMS: To describe characteristics of IBD patients suffering HZV to enable implementation of risk mitigation strategies for those at highest risk. METHODS: Gastroenterologists completed a proforma for IBD patients who experienced HZV infection: IBD phenotype, details of HZV infection, immunosuppression and any change to treatment upon diagnosis of HZV. RESULTS: A total of 30 cases was identified: Crohn disease (CD) (n = 25) and ulcerative colitis (n = 5). In total, 80% (20/25) of the CD patients had penetrating, stricturing or perianal disease. Time from commencement of immunosuppression to HZV infection was highly variable (range: 3 months to over 10 years). A total of 90% (27/30) of patients was on at least one immunosuppressive therapy; of those, one-third was on monotherapy (9/27) and two-thirds (18/27) on dual therapy. A total of 89% (24/27) of immunosupressed patients was on a thiopurine (monotherapy; 6/27) or in combination (18/27). Complications of HZV occurred in 27% (8/30) of patients. CONCLUSION: Our series is consistent with existing epidemiological analysis that identified more severe IBD and the use of multiple immunosuppressive therapies as risk factors for HZV. If the promise of an investigational subunit HZV vaccine is realised in immunocompromised patients, better protection may be possible in the future. Thiopurine medications were the most commonly used immunosuppressant in this series. Age and duration of immunosuppressive therapy do not appear to predict HZV infection.


Assuntos
Herpes Zoster/epidemiologia , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3 , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Vacina contra Herpes Zoster/uso terapêutico , Humanos , Hospedeiro Imunocomprometido/efeitos dos fármacos , Hospedeiro Imunocomprometido/fisiologia , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
15.
J Infect Chemother ; 22(11): 738-743, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27615155

RESUMO

Pulmonary nocardiosis is a rare but potentially serious infection typically in immunosuppressed patients (ISPs). It is also known to occur in immunocompetent patients (ICPs). However, little is currently known regarding the clinical characteristics and radiographic findings of pulmonary nocardiosis specifically in ICPs. In this study, 30 patients with pulmonary nocardiosis were identified and 10 were considered to be colonized. Of all patients with pulmonary nocardiosis, 12 patients were ICPs and 18 were ISPs. Although half of ISPs were infected by Nocardia nova, ICPs were affected by various Nocardia species. Compared with ISPs, chest CT findings of ICPs showed a higher prevalence of bronchiectasis (67% vs 6%, p < .01) and centrilobular nodular opacities (67% vs 11%, p < .01), both of which are often seen in pulmonary nontuberculous mycobacterial disease. Additionally, nontuberculous mycobacterium was isolated from 6 of 21 ICPs with positive Nocardia species culture. Therefore, we recommend that physicians carefully differentiate pulmonary nocardiosis from pulmonary nontuberculous mycobacterial disease in ICPs.


Assuntos
Nocardiose/microbiologia , Nocardiose/patologia , Idoso , Feminino , Humanos , Imunocompetência , Hospedeiro Imunocomprometido/fisiologia , Pulmão/microbiologia , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/microbiologia , Infecções por Mycobacterium não Tuberculosas/patologia , Nocardia/isolamento & purificação , Micobactérias não Tuberculosas/isolamento & purificação , Prevalência , Estudos Retrospectivos
16.
J Gen Virol ; 96(Pt 1): 131-143, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25312585

RESUMO

Graft rejection in transplant patients is managed clinically by suppressing T-cell function with immunosuppressive drugs such as prednisolone and methylprednisolone. In such immunocompromised hosts, human cytomegalovirus (HCMV) is an important opportunistic pathogen and can cause severe morbidity and mortality. Currently, the effect of glucocorticosteroids (GCSs) on the HCMV life cycle remains unclear. Previous reports showed enhanced lytic replication of HCMV in vitro in the presence of GCSs. In the present study, we explored the implications of steroid exposure on latency and reactivation. We observed a direct effect of several GCSs used in the clinic on the activation of a quiescent viral major immediate-early promoter in stably transfected THP-1 monocytic cells. This activation was prevented by the glucocorticoid receptor (GR) antagonist Ru486 and by shRNA-mediated knockdown of the GR. Consistent with this observation, prednisolone treatment of latently infected primary monocytes resulted in HCMV reactivation. Analysis of the phenotype of these cells showed that treatment with GCSs was correlated with differentiation to an anti-inflammatory macrophage-like cell type. On the basis that these observations may be pertinent to HCMV reactivation in post-transplant settings, we retrospectively evaluated the incidence, viral kinetics and viral load of HCMV in liver transplant patients in the presence or absence of GCS treatment. We observed that combination therapy of baseline prednisolone and augmented methylprednisolone, upon organ rejection, significantly increased the incidence of HCMV infection in the intermediate risk group where donor and recipient are both HCMV seropositive (D+R+) to levels comparable with the high risk D+R- group.


Assuntos
Infecções por Citomegalovirus/metabolismo , Citomegalovirus/fisiologia , Glucocorticoides/metabolismo , Fígado/virologia , Células Mieloides/virologia , Ativação Viral/fisiologia , Latência Viral/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular/fisiologia , Linhagem Celular , Doenças Transmissíveis/metabolismo , Doenças Transmissíveis/virologia , Infecções por Citomegalovirus/virologia , Feminino , Humanos , Hospedeiro Imunocomprometido/fisiologia , Fígado/metabolismo , Transplante de Fígado/métodos , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Monócitos/virologia , Células Mieloides/metabolismo , Receptores de Glucocorticoides/metabolismo , Carga Viral/fisiologia , Adulto Jovem
17.
J Eur Acad Dermatol Venereol ; 29(6): 1141-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25307045

RESUMO

BACKGROUND: SIAscopy (Spectrophotometric Intracutaneous Analysis) enables non-invasive analysis of the skin. OBJECTIVE: We wanted to determine whether SIAscopy is able to detect and differentiate the skin chromophores melanin, collagen and haemoglobin and the influence of immunosuppressive drugs and other known risk factors for non-melanoma skin cancer (NMSC). METHODS: Volunteers and patients were measured by SIAscopy at six spots on sun-exposed and two spots on sun-protected skin. Measurements were transformed by SIAmetrics into arbitrary units and statistically analysed. RESULTS: Melanin was shown to be higher with age (+1.73759 a.u.; P < 0.0001), sun exposure (+47.03998 a.u.; P < 0.0001), immunosuppression (+10.48526 a.u.; P < 0.0001) and lower in males (-26.50952 a.u.; P < 0.0001). Collagen was lower with increasing age (-0.29162 a.u.; P < 0.0001) and sun exposure (-6.85586 a.u.; P < 0.0001) but higher with male sex (+8.34251 a.u.; P < 0.0001) and immunosuppression (+5.79171 a.u.; P = 0.0001). Haemoglobin was lower with increasing age (-0.23833 a.u.; P = 0.0005), but higher with male sex (+18.51976 a.u.; P < 0.0001) and sun exposure (+13.74523 a.u.; P < 0.0001). Haemoglobin content was not associated to immunosuppression. CONCLUSION: Our results encourage the use of SIAscopy as a tool to better gauge an individual patient's NMSC risk factors. Further studies should help to better delineate SIAscopy as a prognostic tool.


Assuntos
Colágeno/análise , Hemoglobinas/análise , Hospedeiro Imunocomprometido , Melaninas/análise , Envelhecimento da Pele , Pele/química , Adulto , Fatores Etários , Análise de Variância , Exposição Ambiental , Feminino , Humanos , Hospedeiro Imunocomprometido/fisiologia , Imunossupressores/uso terapêutico , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Envelhecimento da Pele/fisiologia , Espectrofotometria/métodos , Raios Ultravioleta , População Branca , Adulto Jovem
18.
Pediatr Dermatol ; 32(4): e186-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25973735

RESUMO

Achromobacter xylosoxidans is a rare, opportunistic infection most commonly encountered in immunocompromised patients during hospitalization. Primary uncomplicated bacteremia, catheter-associated infections, and pneumonia have been reported as the most common clinical presentations; skin and soft tissue infections from A. xylosoxidans are rare. We describe a case of A. xylosoxidans presenting as cellulitis and bacteremia in an immunocompromised patient.


Assuntos
Achromobacter denitrificans/isolamento & purificação , Bacteriemia/microbiologia , Celulite (Flegmão)/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Adulto , Antibacterianos/uso terapêutico , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Celulite (Flegmão)/diagnóstico , Celulite (Flegmão)/tratamento farmacológico , Evolução Fatal , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Humanos , Hospedeiro Imunocomprometido/fisiologia , Masculino , Pescoço/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Choque Séptico , Adulto Jovem
19.
J Neurovirol ; 20(1): 1-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24481784

RESUMO

Infection with various human polyomaviruses (HPyVs) is prevalent, with rates as high as 80 % within the general population. Primary infection occurs during childhood through respiratory or urino-oral transmission. While the majority of individuals exhibit asymptomatic latent infection, those immunocompromised persons are at risk for viral reactivation and disease progression resulting in conditions such as progressive multifocal leukoencephalopathy (PML), trichodysplasia spinulosa, Merkel cell carcinoma, and polyomavirus associated nephropathy. Individuals with altered immune systems due to HIV, organ transplantation, lymphoproliferative diseases, and monoclonal antibody therapy are particularly susceptible to reactivation of various HPyVs. While the specific factors that induce lytic infection have yet to be defined, it is evident that dysfunctional host cellular immune responses allow active infection to occur. Immunosuppressant conditions, such as in chronic alcohol abuse, may serve as added risk factors for reactivation of HPyVs. Since the human HPyV family is rapidly expanding, continuing studies are needed to characterize the role that known and newly discovered HPyVs play in human disease.


Assuntos
Hospedeiro Imunocomprometido/fisiologia , Infecções por Polyomavirus/virologia , Polyomavirus/fisiologia , Latência Viral/fisiologia , Humanos , Infecções por Polyomavirus/complicações
20.
Blood ; 119(26): 6344-53, 2012 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-22596261

RESUMO

A major challenge in allogeneic hematopoietic cell transplantation is how to transfer T-cell immunity without causing graft-versus-host disease (GVHD). Effector memory T cells (CD62L(-)) are a cell subset that can potentially address this challenge because they do not induce GVHD. Here, we investigated how CD62L(-) T cells contributed to phenotypic and functional T-cell reconstitution after transplantation. On transfer into allogeneic recipients, CD62L(-) T cells were activated and expressed multiple cytokines and cytotoxic molecules. CD62L(-) T cells were able to deplete host radioresistant T cells and facilitate hematopoietic engraftment, resulting in enhanced de novo T-cell regeneration. Enhanced functional immune reconstitution was demonstrated in CD62L(-) T-cell recipients using a tumor and an influenza virus challenge model. Even though CD62L(-) T cells are able to respond to alloantigens and deplete host radioresistant immune cells in GVHD recipients, alloreactive CD62L(-) T cells lost the reactivity over time and were eventually tolerant to alloantigens as a result of prolonged antigen exposure, suggesting a mechanism by which CD62L(-) T cells were able to eliminate host resistance without causing GVHD. These data further highlight the unique characteristics of CD62L(-) T cells and their potential applications in clinical hematopoietic cell transplantation.


Assuntos
Proliferação de Células , Transplante de Células-Tronco Hematopoéticas , Memória Imunológica/imunologia , Selectina L/metabolismo , Linfócitos T/fisiologia , Tolerância ao Transplante/imunologia , Animais , Diferenciação Celular/imunologia , Células Cultivadas , Feminino , Imunidade Inata/imunologia , Hospedeiro Imunocomprometido/imunologia , Hospedeiro Imunocomprometido/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos SCID , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transplante Homólogo
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