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1.
Cell ; 182(4): 843-854.e12, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32673567

RESUMO

The SARS-CoV-2 pandemic has unprecedented implications for public health, social life, and the world economy. Because approved drugs and vaccines are limited or not available, new options for COVID-19 treatment and prevention are in high demand. To identify SARS-CoV-2-neutralizing antibodies, we analyzed the antibody response of 12 COVID-19 patients from 8 to 69 days after diagnosis. By screening 4,313 SARS-CoV-2-reactive B cells, we isolated 255 antibodies from different time points as early as 8 days after diagnosis. Of these, 28 potently neutralized authentic SARS-CoV-2 with IC100 as low as 0.04 µg/mL, showing a broad spectrum of variable (V) genes and low levels of somatic mutations. Interestingly, potential precursor sequences were identified in naive B cell repertoires from 48 healthy individuals who were sampled before the COVID-19 pandemic. Our results demonstrate that SARS-CoV-2-neutralizing antibodies are readily generated from a diverse pool of precursors, fostering hope for rapid induction of a protective immune response upon vaccination.


Assuntos
Anticorpos Neutralizantes/isolamento & purificação , Anticorpos Antivirais/isolamento & purificação , Infecções por Coronavirus/imunologia , Pneumonia Viral/imunologia , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/genética , Anticorpos Antivirais/imunologia , Linfócitos B/imunologia , Betacoronavirus/imunologia , COVID-19 , Humanos , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Memória Imunológica , Estudos Longitudinais , Pandemias , SARS-CoV-2 , Hipermutação Somática de Imunoglobulina
3.
J Infect Dis ; 230(2): e327-e332, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-38195212

RESUMO

Licensed vaccines against the Middle East respiratory syndrome coronavirus (MERS-CoV), an emerging pathogen of concern, are lacking. The modified vaccinia virus Ankara vector-based vaccine MVA-MERS-S, expressing the MERS-CoV-spike glycoprotein (MERS-S), is one of 3 candidate vaccines in clinical development and elicits robust humoral and cellular immunity. Here, we identified for the first time a MERS-S-specific CD8+ T-cell epitope in an HLA-A*03:01/HLA-B*35:01-positive vaccinee using a screening assay, intracellular cytokine staining, and in silico epitope prediction. As evidence from MERS-CoV infection suggests a protective role of long-lasting CD8+ T-cell responses, the identification of epitopes will facilitate longitudinal analyses of vaccine-induced T-cell immunity.


Assuntos
Linfócitos T CD8-Positivos , Epitopos de Linfócito T , Coronavírus da Síndrome Respiratória do Oriente Médio , Glicoproteína da Espícula de Coronavírus , Vacinas Virais , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Epitopos de Linfócito T/imunologia , Linfócitos T CD8-Positivos/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Vacinação
4.
Euro Surveill ; 29(5)2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38304950

RESUMO

Airport malaria is uncommon but increasing in Europe and often difficult to diagnose. We describe the clinical, epidemiological and environmental investigations of a cluster of airport malaria cases and measures taken in response. Three Frankfurt International Airport employees without travel histories to malaria-endemic areas were diagnosed with Plasmodium falciparum malaria in Germany in 2022. Two cases were diagnosed within 1 week, and the third one after 10 weeks. Two cases had severe disease, all three recovered fully. The cases worked in separate areas and no specific location for the transmissions could be identified. No additional cases were detected among airport employees. In June and July, direct flights from Equatorial Guinea, Nigeria and Angola and one parcel originating in Ghana arrived at Frankfurt airport. No vector-competent mosquitoes could be trapped to identify the source of the outbreak. Whole genome sequencing of P. falciparum genomes showed a high genetic relatedness between samples of the three cases and suggested the geographical origin closest to Ghana. A diagnosis of airport malaria should prompt appropriate and comprehensive outbreak investigations to identify the source and to prevent severe forms of falciparum malaria.


Assuntos
Malária Falciparum , Malária , Animais , Humanos , Aeroportos , Viagem , Malária Falciparum/diagnóstico , Malária Falciparum/epidemiologia , Malária/epidemiologia , Alemanha/epidemiologia , Plasmodium falciparum/genética
5.
Infection ; 51(5): 1563-1568, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37273167

RESUMO

BACKGROUND: In May 2022, a multi-national mpox outbreak was reported in several non-endemic countries. The only licensed treatment for mpox in the European Union is the orally available small molecule tecovirimat, which in Orthopox viruses inhibits the function of a major envelope protein required for the production of extracellular virus. METHODS: We identified presumably all patients with mpox that were treated with tecovirimat in Germany between the onset of the outbreak in May 2022 and March 2023 and obtained demographic and clinical characteristics by standardized case report forms. RESULTS: A total of twelve patients with mpox were treated with tecovirimat in Germany in the study period. All but one patient identified as men who have sex with men (MSM) who were most likely infected with mpox virus (MPXV) through sexual contact. Eight of them were people living with HIV (PLWH), one of whom was newly diagnosed with HIV at the time of mpox, and four had CD4+ counts below 200/µl. Criteria for treatment with tecovirimat included severe immunosuppression, severe generalized and/or protracted symptoms, a high or increasing number of lesions, and the type and location of lesions (e.g., facial or oral soft tissue involvement, imminent epiglottitis, or tonsillar swelling). Patients were treated with tecovirimat for between six and 28 days. Therapy was generally well-tolerated, and all patients showed clinical resolution. CONCLUSIONS: In this cohort of twelve patients with severe mpox, treatment with tecovirimat was well tolerated and all individuals showed clinical improvement.


Assuntos
Infecções por HIV , Mpox , Minorias Sexuais e de Gênero , Masculino , Humanos , Homossexualidade Masculina , Alemanha/epidemiologia , Benzamidas
6.
Ann Intern Med ; 175(8): 1126-1134, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35667065

RESUMO

BACKGROUND: In the MOVe-OUT trial, molnupiravir showed a clinically meaningful reduction in the risk for hospitalization or death in adults with mild to moderate COVID-19 and risk factors for progression to severe disease. OBJECTIVE: To identify other potential clinical benefits of molnupiravir versus placebo. DESIGN: Secondary analysis of the randomized, double-blind, placebo-controlled phase 3 component of MOVe-OUT. (ClinicalTrials.gov: NCT04575597). SETTING: 107 sites globally. PARTICIPANTS: 1433 nonhospitalized adults aged 18 years or older with mild to moderate COVID-19. INTERVENTION: Molnupiravir, 800 mg, or placebo every 12 hours for 5 days. MEASUREMENTS: Changes from baseline in C-reactive protein (CRP) concentration and oxygen saturation (Spo 2), need for respiratory interventions (including invasive mechanical ventilation), and need for medical services in all randomly assigned participants through day 29, and need for respiratory interventions and time to discharge in the subgroup of participants who were hospitalized after randomization. RESULTS: Participants receiving molnupiravir showed faster normalization of CRP and Spo 2, with improvements observed on day 3 of therapy, compared with placebo. Molnupiravir-treated participants had a decreased need for respiratory interventions versus placebo-treated participants (relative risk reduction [RRR], 34.3% [95% CI, 4.3% to 54.9%]), with similar findings in participants who were hospitalized after randomization (RRR, 21.3% [CI, 0.2% to 38.0%]). Hospitalized participants who received molnupiravir were discharged a median of 3 days before those who received placebo. Acute care visits (7.2% vs. 10.6%; RRR, 32.1% [CI, 4.4% to 51.7%]) and COVID-19-related acute care visits (6.6% vs. 10.0%; RRR, 33.8% [CI, 5.6% to 53.6%]) were less frequent in molnupiravir- versus placebo-treated participants. LIMITATIONS: Some analyses were performed post hoc. Longer-term benefits of molnupiravir therapy were not evaluated. Participants were not immunized against SARS-CoV-2. CONCLUSION: The findings suggest there are additional important clinical benefits of molnupiravir beyond reduction in hospitalization or death. PRIMARY FUNDING SOURCE: Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc.


Assuntos
COVID-19 , Adulto , Biomarcadores , COVID-19/terapia , Citidina/análogos & derivados , Método Duplo-Cego , Humanos , Hidroxilaminas , Respiração Artificial , SARS-CoV-2 , Resultado do Tratamento
7.
Clin Infect Dis ; 74(4): 729-733, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34318871

RESUMO

Emerging infectious disease epidemics require a rapid response from health systems; however, evidence-based consensus guidelines are generally absent early in the course of events. Formed in 2017 by 5 high-level isolation units spanning 3 continents, the experience of the Global Infectious Disease Preparedness Network (GIDPN) early in the course of coronavirus disease 2019 (COVID-19) provides a model for accelerating best practice development and improving decision-making in health emergencies. The network served as a platform for real-time, open and transparent information-sharing during unknowns of an active outbreak by clinicians caring for patients, by researchers conducting clinical trials and transmission and infection prevention studies, and by teams advising local and national policy makers. Shared knowledge led to earlier adoption of some treatment modalities as compared to most peer institutions and to implementation of protocols prior to incorporation into national guidelines. GIDPN and similar networks are integral in enhancing preparedness for and response to future epidemics/pandemics.


Assuntos
COVID-19 , Doenças Transmissíveis , Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/terapia , Tomada de Decisões , Humanos , Pandemias/prevenção & controle , SARS-CoV-2
8.
J Infect Dis ; 224(7): 1109-1114, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34223909

RESUMO

Whether monoclonal antibodies are able to neutralize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern has been investigated using pseudoviruses. In this study we show that bamlanivimab, casirivimab, and imdevimab efficiently neutralize authentic SARS-CoV-2, including variant B.1.1.7 (alpha), but variants B.1.351 (beta) and P.2 (zeta) were resistant against bamlanivimab and partially resistant to casirivimab. Whether antibodies are able to neutralize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variantshas been investigated using pseudoviruses. We show that authentic SARS-CoV-2 carrying E484K were resistant against bamlanivimab and less susceptible to casirivimab, convalescent and vaccine-elicited sera.


Assuntos
COVID-19/virologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Substituição de Aminoácidos , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Humanos , Mutação de Sentido Incorreto , Testes de Neutralização
9.
J Infect Dis ; 223(1): 56-61, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33128369

RESUMO

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has caused a pandemic with tens of millions of cases and hundreds of thousands of deaths. The infection causes coronavirus disease 2019 (COVID-19), a disease of the respiratory system of divergent severity. In the current study, humoral immune responses were characterized in a cohort of 143 patients with COVID-19 from the University Hospital Frankfurt am Main, Germany. METHODS: SARS-CoV-2-specific-antibodies were detected by enzyme-linked immunosorbent assay (ELISA). SARS-CoV-2 and human coronavirus NL63 neutralization activity was analyzed with pseudotyped lentiviral vectors. RESULTS: The severity of COVID-19 increased with age, and male patients encountered more serious symptoms than female patients. Disease severity was correlated with the amount of SARS-CoV-2-specific immunoglobulin (Ig) G and IgA and the neutralization activity of the antibodies. The amount of SARS-CoV-2-specific IgG antibodies decreased with time after polymerase chain reaction conformation of the infection, and antibodies directed against the nucleoprotein waned faster than spike protein-directed antibodies. In contrast, for the common flu coronavirus NL63, COVID-19 disease severity seemed to be correlated with low NL63-neutralizing activities, suggesting the possibility of cross-reactive protection. CONCLUSION: The results describe the humoral immune responses against SARS-CoV-2 and might aid the identification of correlates of protection needed for vaccine development.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , Imunidade Humoral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/imunologia , Estudos de Coortes , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Feminino , Alemanha , Células HEK293 , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
J Clin Microbiol ; 58(12)2020 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-32938741

RESUMO

Mycobacterium abscessus is a highly antibiotic-resistant opportunistic pathogen causing clinically challenging infections in patients with preexisting lung diseases or under immunosuppression. Hence, reliable antibiotic susceptibility data are required for effective treatment. Aims of this study were to investigate (i) the congruence of genotypic and phenotypic antimicrobial susceptibility testing, (ii) the relationship between resistance profile and clinical course, and (iii) the phylogenetic relations of M. abscessus in a German patient cohort. A total of 39 isolates from 29 patients infected or colonized with M. abscessus underwent genotypic and phenotypic drug susceptibility testing. Clinical data were correlated with susceptibility data. Phylogenetic analysis was performed by means of whole-genome sequencing (WGS) and single-nucleotide polymorphism (SNP) analysis. Macrolide resistance was mainly mediated by functional Erm(41) methyltransferases (T28 sequevars) in M. abscessus subsp. abscessus (n = 25) and M. abscessus subsp. bolletii (n = 2). It was significantly associated with impaired culture conversion (P = 0.02). According to the core SNP phylogeny, we identified three clusters of closely related isolates with SNP distances below 25. Representatives of all circulating global clones (Absc. 1, Absc. 2, and Mass. 1) were identified in our cohort. However, we could not determine evidence for in-hospital interhuman transmission from clinical data. In our patient cohort, we identified three M. abscessus clusters with closely related isolates and representatives of the previously described international clusters but no human-to-human in-hospital transmission. Macrolide and aminoglycoside susceptibility data are critical for therapeutic decision-making in M. abscessus infections.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Mycobacterium abscessus , Mycobacterium tuberculosis , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Claritromicina/farmacologia , Farmacorresistência Bacteriana/genética , Humanos , Macrolídeos/farmacologia , Testes de Sensibilidade Microbiana , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Mycobacterium abscessus/genética , Filogenia
12.
Appl Microbiol Biotechnol ; 104(21): 9283-9294, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32989516

RESUMO

Actinoplanes sp. SE50/110 is the industrially relevant producer of acarbose, which is used in the treatment of diabetes mellitus. Recent studies elucidated the expression dynamics in Actinoplanes sp. SE50/110 during growth. From these data, we obtained a large genomic region (ACSP50_3900 to ACSP50_3950) containing 51 genes, of which 39 are transcribed in the same manner. These co-regulated genes were found to be stronger transcribed on maltose compared with glucose as a carbon source. The transcriptional regulator MalT was identified as an activator of this maltose-regulated large genomic region (MRLGR). Since most of the genes are poorly annotated, the function of this region is farther unclear. However, comprehensive BLAST analyses indicate similarities to enzymes involved in amino acid metabolism. We determined a conserved binding motif of MalT overlapping the -35 promoter region of 17 transcription start sites inside the MRLGR. The corresponding sequence motif 5'-TCATCC-5nt-GGATGA-3' displays high similarities to reported MalT binding sites in Escherichia coli and Klebsiella pneumoniae, in which MalT is the activator of mal genes. A malT deletion and an overexpression mutant were constructed. Differential transcriptome analyses revealed an activating effect of MalT on 40 of the 51 genes. Surprisingly, no gene of the maltose metabolism is affected. In contrast to many other bacteria, MalT is not the activator of mal genes in Actinoplanes sp. SE50/110. Finally, the MRLGR was found partly in other closely related bacteria of the family Micromonosporaceae. Even the conserved MalT binding site was found upstream of several genes inside of the corresponding regions. KEY POINTS : • MalT is the maltose-dependent activator of a large genomic region in ACSP50_WT. • The consensus binding motif is similar to MalT binding sites in other bacteria. • MalT is not the regulator of genes involved in maltose metabolism in ACSP50_WT.


Assuntos
Actinoplanes , Micromonosporaceae , Acarbose , Proteínas de Bactérias/genética , Genômica , Maltose , Micromonosporaceae/genética
13.
N Engl J Med ; 374(7): 636-46, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26886522

RESUMO

BACKGROUND: Available data on the characteristics of patients with Ebola virus disease (EVD) and clinical management of EVD in settings outside West Africa, as well as the complications observed in those patients, are limited. METHODS: We reviewed available clinical, laboratory, and virologic data from all patients with laboratory-confirmed Ebola virus infection who received care in U.S. and European hospitals from August 2014 through December 2015. RESULTS: A total of 27 patients (median age, 36 years [range, 25 to 75]) with EVD received care; 19 patients (70%) were male, 9 of 26 patients (35%) had coexisting conditions, and 22 (81%) were health care personnel. Of the 27 patients, 24 (89%) were medically evacuated from West Africa or were exposed to and infected with Ebola virus in West Africa and had onset of illness and laboratory confirmation of Ebola virus infection in Europe or the United States, and 3 (11%) acquired EVD in the United States or Europe. At the onset of illness, the most common signs and symptoms were fatigue (20 patients [80%]) and fever or feverishness (17 patients [68%]). During the clinical course, the predominant findings included diarrhea, hypoalbuminemia, hyponatremia, hypokalemia, hypocalcemia, and hypomagnesemia; 14 patients (52%) had hypoxemia, and 9 (33%) had oliguria, of whom 5 had anuria. Aminotransferase levels peaked at a median of 9 days after the onset of illness. Nearly all the patients received intravenous fluids and electrolyte supplementation; 9 (33%) received noninvasive or invasive mechanical ventilation; 5 (19%) received continuous renal-replacement therapy; 22 (81%) received empirical antibiotics; and 23 (85%) received investigational therapies (19 [70%] received at least two experimental interventions). Ebola viral RNA levels in blood peaked at a median of 7 days after the onset of illness, and the median time from the onset of symptoms to clearance of viremia was 17.5 days. A total of 5 patients died, including 3 who had respiratory and renal failure, for a mortality of 18.5%. CONCLUSIONS: Among the patients with EVD who were cared for in the United States or Europe, close monitoring and aggressive supportive care that included intravenous fluid hydration, correction of electrolyte abnormalities, nutritional support, and critical care management for respiratory and renal failure were needed; 81.5% of these patients who received this care survived.


Assuntos
Antibacterianos/uso terapêutico , Ebolavirus/isolamento & purificação , Hidratação , Doença pelo Vírus Ebola/terapia , Adulto , Idoso , Terapia Combinada , Cuidados Críticos , Ebolavirus/genética , Eletrólitos/uso terapêutico , Europa (Continente) , Feminino , Doença pelo Vírus Ebola/complicações , Doença pelo Vírus Ebola/mortalidade , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Respiração Artificial , Índice de Gravidade de Doença , Transaminases/sangue , Estados Unidos , Carga Viral
14.
Infection ; 47(5): 817-825, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31093923

RESUMO

PURPOSE: NTM are ubiquitous bacteria that can cause colonisation and infection in immunocompetent and compromised hosts. The aim of this study was to elucidate the epidemiology of infection or colonisation with NTM for the metropolitan region of Frankfurt, Germany. METHODS: All patients from whom NTM were isolated within the period from 2006 to 2016 were included in this retrospective analysis. Patient data were retrieved using the local patient data management system. Different groups were formed according to clinical manifestations, underlying diseases and mycobacterial species. They were compared in regard to mortality, duration of infection/colonisation and their geographical origins. RESULTS: A total of 297 patients with a median of 28 new patients each year were included. Most patients suffered from lung infection or colonisation (72.7%, n = 216), followed by disseminated mycobacteriosis (12.5%, n = 37). The majority were HIV-positive, suffering from malignoma or cystic fibrosis (29.3%, n = 87, 16.2%, n = 48, and 13.8%, n = 41, respectively). 17.2% of patients showed no predisposing condition (n = 51). Mycobacterium avium complex (MAC) species were most frequently isolated (40.7%, n = 121). Infection/colonisation was longest in CF patients (median of 1094 days). The mortality was highest in malignoma patients (52.4%), while CF patients had the lowest overall mortality rate (5.3%). But mortality analysis showed non-significant results within different mycobacterial species and clinical manifestations. CONCLUSION: NTM remain rare but underestimated pathogens in lung and disseminated disease. MAC were the species most frequently isolated. Depending on species and underlying predispositions, the duration of infection/colonisation can be unexpectedly long.


Assuntos
Infecções por Mycobacterium não Tuberculosas/epidemiologia , Micobactérias não Tuberculosas/patogenicidade , Centros de Atenção Terciária , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cidades , Fibrose Cística/epidemiologia , Fibrose Cística/microbiologia , Feminino , Alemanha/epidemiologia , Soropositividade para HIV/epidemiologia , Soropositividade para HIV/microbiologia , Humanos , Pulmão/microbiologia , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/mortalidade , Complexo Mycobacterium avium/patogenicidade , Neoplasias/epidemiologia , Neoplasias/microbiologia , Micobactérias não Tuberculosas/classificação , Estudos Retrospectivos , Adulto Jovem
15.
Euro Surveill ; 24(49)2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31822328

RESUMO

Two cases of presumably airport-acquired falciparum malaria were diagnosed in Frankfurt in October 2019. They were associated with occupation at the airport, and Plasmodium falciparum parasites from their blood showed genetically identical microsatellite and allele patterns. Both had severe malaria. It took more than a week before the diagnosis was made. If symptoms are indicative and there is a plausible exposure, malaria should be considered even if patients have not travelled to an endemic area.


Assuntos
Malária Falciparum/diagnóstico , Plasmodium falciparum/isolamento & purificação , Adulto , Aeroportos , Antimaláricos/uso terapêutico , Artesunato/uso terapêutico , Atovaquona/uso terapêutico , Febre/etiologia , Genótipo , Alemanha , Humanos , Malária Falciparum/sangue , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Masculino , Pessoa de Meia-Idade , Plasmodium falciparum/genética , Reação em Cadeia da Polimerase , Proguanil/uso terapêutico , Viagem , Resultado do Tratamento
18.
Haematologica ; 103(5): 857-864, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29439188

RESUMO

Outcome of HIV-infected patients with AIDS-related lymphomas has improved during recent years. However, data on incidence, risk factors, and outcome of relapses in AIDS-related lymphomas after achieving complete remission are still limited. This prospective observational multicenter study includes HIV-infected patients with biopsy- or cytology-proven malignant lymphomas since 2005. Data on HIV infection and lymphoma characteristics, treatment and outcome were recorded. For this analysis, AIDS-related lymphomas patients in complete remission were analyzed in terms of their relapse- free survival and potential risk factors for relapses. In total, 254 of 399 (63.7%) patients with AIDS-related lymphomas reached a complete remission with their first-line chemotherapy. After a median follow up of 4.6 years, 5-year overall survival of the 254 patients was 87.8% (Standard Error 3.1%). Twenty-nine patients relapsed (11.4%). Several factors were independently associated with a higher relapse rate, including an unclassifiable histology, a stage III or IV according to the Ann Arbor Staging System, no concomitant combined antiretroviral therapy during chemotherapy and R-CHOP-based compared to more intensive chemotherapy regimens in Burkitt lymphomas. In conclusion, complete remission and relapse rates observed in our study are similar to those reported in HIV-negative non-Hodgkin lymphomas. These data provide further evidence for the use of concomitant combined antiretroviral therapy during chemotherapy and a benefit from more intensive chemotherapy regimens in Burkitt lymphomas. Modifications to the chemotherapy regimen appear to have only a limited impact on relapse rate.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Linfoma Relacionado a AIDS/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Recidiva Local de Neoplasia/induzido quimicamente , Recidiva Local de Neoplasia/epidemiologia , Adulto , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Incidência , Linfoma Relacionado a AIDS/patologia , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Indução de Remissão , Fatores de Risco , Taxa de Sobrevida
20.
BMC Genomics ; 18(1): 562, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28743243

RESUMO

BACKGROUND: Acarbose is used in the treatment of diabetes mellitus type II and is produced by Actinoplanes sp. SE50/110. Although the biosynthesis of acarbose has been intensively studied, profound knowledge about transcription factors involved in acarbose biosynthesis and their binding sites has been missing until now. In contrast to acarbose biosynthetic gene clusters in Streptomyces spp., the corresponding gene cluster of Actinoplanes sp. SE50/110 lacks genes for transcriptional regulators. RESULTS: The acarbose regulator C (AcrC) was identified through an in silico approach by aligning the LacI family regulators of acarbose biosynthetic gene clusters in Streptomyces spp. with the Actinoplanes sp. SE50/110 genome. The gene for acrC, located in a head-to-head arrangement with the maltose/maltodextrin ABC transporter malEFG operon, was deleted by introducing PCR targeting for Actinoplanes sp. SE50/110. Characterization was carried out through cultivation experiments, genome-wide microarray hybridizations, and RT-qPCR as well as electrophoretic mobility shift assays for the elucidation of binding motifs. The results show that AcrC binds to the intergenic region between acbE and acbD in Actinoplanes sp. SE50/110 and acts as a transcriptional repressor on these genes. The transcriptomic profile of the wild type was reconstituted through a complementation of the deleted acrC gene. Additionally, regulatory sequence motifs for the binding of AcrC were identified in the intergenic region of acbE and acbD. It was shown that AcrC expression influences acarbose formation in the early growth phase. Interestingly, AcrC does not regulate the malEFG operon. CONCLUSIONS: This study characterizes the first known transcription factor of the acarbose biosynthetic gene cluster in Actinoplanes sp. SE50/110. It therefore represents an important step for understanding the regulatory network of this organism. Based on this work, rational strain design for improving the biotechnological production of acarbose can now be implemented.


Assuntos
Acarbose/metabolismo , Actinobacteria/genética , Actinobacteria/metabolismo , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Proteínas Repressoras/metabolismo , Transcrição Gênica , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Genômica , Família Multigênica/genética , Proteínas Repressoras/química , Proteínas Repressoras/genética , Deleção de Sequência
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