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Demars M, McDowell T, Renaud JB, Scott A, Fruci M, Topp E. Persistence and evidence for accelerated biodegradation of streptomycin in agricultural soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 929:172502. [PMID: 38636872 DOI: 10.1016/j.scitotenv.2024.172502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 04/12/2024] [Accepted: 04/13/2024] [Indexed: 04/20/2024]
Abstract
Some antibiotics are used for the treatment of various bacterial crop diseases, and there is a concern that this practice may represent a selection pressure that increases the reservoir of antibiotic resistance carried by bacteria in crop production systems. Since the 1950s the aminoglycoside antibiotic streptomycin has been widely used for the treatment of some bacterial crop diseases such as fire blight in apples and pears. Following application, the time that bacteria will be exposed to the antibiotic, and therefore the pressure for selection of resistance, will vary according to the environmental persistence of the antibiotic. In the present study, the dissipation of streptomycin was examined in soils supplemented with 5 mg streptomycin/kg soil and incubated for 21 days under laboratory conditions. The impact of two key rate-controlling variables, soil texture (sandy loam, loam, clay loam) and temperature (4, 20, 30 °C) on streptomycin persistence were explored. -Robust methods for streptomycin extraction and analysis by LC-MS/MS were developed. Streptomycin dissipation followed first order kinetics, with the time to dissipate 50 % of the parent compound (DT50) in soils of varying texture incubated at 20 °C ranging from about seven to 15 days. In contrast, the DT50 of streptomycin in autoclaved loam soil incubated at 20 °C was about 111 days. At 4 °C the DT50 ranged from 49 to 137 days. Under no incubation conditions were any extractable transformation products obtained. Streptomycin was dissipated significantly more rapidly in field soil that had a prior history of exposure to the antibiotic than in soil that did not. Taken together, these results indicate that streptomycin is amenable to biodegradation in agricultural soils with DT50s of several days when temperature is permissive.
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Affiliation(s)
- Megan Demars
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada; Department of Biology, University of Western Ontario, London, ON, Canada
| | - Tim McDowell
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada
| | - Justin B Renaud
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada
| | - Andrew Scott
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada
| | - Michael Fruci
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada; Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada
| | - Edward Topp
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada; Department of Biology, University of Western Ontario, London, ON, Canada.
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Whiles S, Zhang Q, Chamberlain Z, Singh MK, Steele S, Zheng L, Rosche K, Huang W, Gao H, Zhang Q, Kawula T. Discovery of D8-03 as an Inhibitor of Intracellular Growth of Francisella tularensis. ACS Infect Dis 2024. [PMID: 38876983 DOI: 10.1021/acsinfecdis.4c00116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2024]
Abstract
Francisella tularensis is a Gram-negative facultative intracellular bacterial pathogen that is classified by the Centers for Disease Control and Prevention as a Tier 1 Select Agent. F. tularensis infection causes the disease tularemia, also known as rabbit fever. Treatment of tularemia is limited to few effective antibiotics which are associated with high relapse rates, toxicity, and potential emergence of antibiotic-resistant strains. Consequently, new therapeutic options for tularemia are needed. Through screening a focused chemical library and subsequent structure-activity relationship studies, we have discovered a new and potent inhibitor of intracellular growth of Francisella tularensis, D8-03. Importantly, D8-03 effectively reduces bacterial burden in mice infected with F. tularensis. Preliminary mechanistic investigations suggest that D8-03 works through a potentially novel host-dependent mechanism and serves as a promising lead compound for further development.
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Affiliation(s)
- Shannon Whiles
- Paul G. Allen School for Global Health, Washington State University, Pullman, Washington 99164, United States
| | - Quanzheng Zhang
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Zach Chamberlain
- Paul G. Allen School for Global Health, Washington State University, Pullman, Washington 99164, United States
| | - Manish K Singh
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Shaun Steele
- Paul G. Allen School for Global Health, Washington State University, Pullman, Washington 99164, United States
| | - Linda Zheng
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Kristin Rosche
- Program in Vector-borne Disease, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington 99164, United States
| | - Weigang Huang
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Huanyao Gao
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Qisheng Zhang
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Thomas Kawula
- Paul G. Allen School for Global Health, Washington State University, Pullman, Washington 99164, United States
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Hahn MM, Triplett CA, Anderson MS, Smart JI, Litherland K, Keech S, von Siebenthal F, Jones M, Phipps AJ, Henning LN. Ceftobiprole Medocaril Is an Effective Post-Exposure Treatment in the Fischer 344 Rat Model of Pneumonic Tularemia. Antibiotics (Basel) 2023; 12:1337. [PMID: 37627757 PMCID: PMC10451734 DOI: 10.3390/antibiotics12081337] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 07/19/2023] [Accepted: 08/16/2023] [Indexed: 08/27/2023] Open
Abstract
Francisella tularensis subspecies tularensis is a category-A biothreat agent that can cause lethal tularemia. Ceftobiprole medocaril is being explored as a medical countermeasure for the treatment of pneumonic tularemia. The efficacy of ceftobiprole medocaril against inhalational tularemia was evaluated in the Fischer 344 rat model of infection. The dose was expected to be effective against F. tularensis isolates with ceftobiprole minimum inhibitory concentrations ≤0.5 µg/mL. Animals treated with ceftobiprole medocaril exhibited a 92% survival rate 31 days post-challenge, identical to the survival of levofloxacin-treated rats. By comparison, rats receiving placebo experienced 100% mortality. Terminally collected blood, liver, lung, and spleen samples confirmed disseminated F. tularensis infections in most animals that died prior to completing treatments (placebo animals and a rat treated with ceftobiprole medocaril), although levels of bacteria detected in the placebo samples were significantly elevated compared to the ceftobiprole-medocaril-treated group geometric mean. Furthermore, no evidence of infection was detected in any rat that completed ceftobiprole medocaril or levofloxacin treatment and survived to the end of the post-treatment observation period. Overall, survival rates, body weights, and bacterial burdens consistently demonstrated that treatment with ceftobiprole medocaril is efficacious against otherwise fatal cases of pneumonic tularemia in the rat model.
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Affiliation(s)
| | | | | | - Jennifer I. Smart
- Basilea Pharmaceutica International Ltd., 4123 Allschwil, Switzerland
| | - Karine Litherland
- Basilea Pharmaceutica International Ltd., 4123 Allschwil, Switzerland
| | - Stephen Keech
- Basilea Pharmaceutica International Ltd., 4123 Allschwil, Switzerland
| | | | - Mark Jones
- Basilea Pharmaceutica International Ltd., 4123 Allschwil, Switzerland
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Kraft DC, Naeem M, Mansour J, Beal MA, Bailey TC, Bhalla S. Body Imaging of Bacterial and Parasitic Zoonoses: Keys to Diagnosis. Radiographics 2023; 43:e220092. [PMID: 36729948 DOI: 10.1148/rg.220092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Zoonotic infections, which are transmitted from animals to humans, have been a substantial source of human disease since antiquity. As the human population continues to grow and human influence on the planet expands, humans frequently encounter both domestic and wild animals. This has only increased as deforestation, urbanization, agriculture, habitat fragmentation, outdoor recreation, and international travel evolve in modern society, all of which have resulted in the emergence and reemergence of zoonotic infections. Zoonotic infections pose a diagnostic challenge because of their nonspecific clinical manifestations and the need for specialized testing procedures to confirm these diagnoses. Affected patients often undergo imaging during their evaluation, and a radiologist familiar with the specific and often subtle imaging patterns of these infections can add important clinical value. The authors review the multimodality thoracic, abdominal, and musculoskeletal imaging findings of zoonotic bacterial (eg, Bartonella henselae, Pasteurella multocida, Francisella tularensis, Coxiella burnetii, and Brucella species), spirochetal (eg, Leptospira species), and parasitic (eg, Echinococcus, Paragonimus, Toxocara, and Dirofilaria species) infections that are among the more commonly encountered zoonoses in the United States. Relevant clinical, epidemiologic, and pathophysiologic clues such as exposure history, occupational risk factors, and organism life cycles are also reviewed. Although many of the imaging findings of zoonotic infections overlap with those of nonzoonotic infections, granulomatous diseases, and malignancies, radiologists' familiarity with the imaging patterns can aid in the differential diagnosis in a patient with a suspected or unsuspected zoonotic infection. © RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.
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Affiliation(s)
- David C Kraft
- From the Department of Radiology, Baylor University Medical Center, 3500 Gaston Ave, Dallas, Texas 75246-2017 (D.C.K.); Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Ga (M.N.); Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, Ind (J.M.); and Mallinckrodt Institute of Radiology (M.A.B., S.B.) and Department of Infectious Diseases (T.C.B.), Washington University School of Medicine, St Louis, Mo
| | - Muhammad Naeem
- From the Department of Radiology, Baylor University Medical Center, 3500 Gaston Ave, Dallas, Texas 75246-2017 (D.C.K.); Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Ga (M.N.); Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, Ind (J.M.); and Mallinckrodt Institute of Radiology (M.A.B., S.B.) and Department of Infectious Diseases (T.C.B.), Washington University School of Medicine, St Louis, Mo
| | - Joseph Mansour
- From the Department of Radiology, Baylor University Medical Center, 3500 Gaston Ave, Dallas, Texas 75246-2017 (D.C.K.); Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Ga (M.N.); Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, Ind (J.M.); and Mallinckrodt Institute of Radiology (M.A.B., S.B.) and Department of Infectious Diseases (T.C.B.), Washington University School of Medicine, St Louis, Mo
| | - Michael A Beal
- From the Department of Radiology, Baylor University Medical Center, 3500 Gaston Ave, Dallas, Texas 75246-2017 (D.C.K.); Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Ga (M.N.); Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, Ind (J.M.); and Mallinckrodt Institute of Radiology (M.A.B., S.B.) and Department of Infectious Diseases (T.C.B.), Washington University School of Medicine, St Louis, Mo
| | - Thomas C Bailey
- From the Department of Radiology, Baylor University Medical Center, 3500 Gaston Ave, Dallas, Texas 75246-2017 (D.C.K.); Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Ga (M.N.); Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, Ind (J.M.); and Mallinckrodt Institute of Radiology (M.A.B., S.B.) and Department of Infectious Diseases (T.C.B.), Washington University School of Medicine, St Louis, Mo
| | - Sanjeev Bhalla
- From the Department of Radiology, Baylor University Medical Center, 3500 Gaston Ave, Dallas, Texas 75246-2017 (D.C.K.); Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Ga (M.N.); Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, Ind (J.M.); and Mallinckrodt Institute of Radiology (M.A.B., S.B.) and Department of Infectious Diseases (T.C.B.), Washington University School of Medicine, St Louis, Mo
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Iron-Modified Blood Culture Media Allow for the Rapid Diagnosis and Isolation of the Slow-Growing Pathogen Francisella tularensis. Microbiol Spectr 2022; 10:e0241522. [PMID: 36190401 PMCID: PMC9603284 DOI: 10.1128/spectrum.02415-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The life-threatening disease tularemia is caused by Francisella tularensis, an intracellular Gram-negative bacterial pathogen. Due to the high mortality rates of the disease, as well as the low respiratory infectious dose, F. tularensis is categorized as a Tier 1 bioterror agent. The identification and isolation from clinical blood cultures of F. tularensis are complicated by its slow growth. Iron was shown to be one of the limiting nutrients required for F. tularensis metabolism and growth. Bacterial growth was shown to be restricted or enhanced in the absence or addition of iron. In this study, we tested the beneficial effect of enhanced iron concentrations on expediting F. tularensis blood culture diagnostics. Accordingly, bacterial growth rates in blood cultures with or without Fe2+ supplementation were evaluated. Growth quantification by direct CFU counts demonstrated significant improvement of growth rates of up to 6 orders of magnitude in Fe2+-supplemented media compared to the corresponding nonmodified cultures. Fe2+ supplementation significantly shortened incubation periods for successful diagnosis and isolation of F. tularensis by up to 92 h. This was achieved in a variety of blood culture types in spite of a low initial bacterial inoculum representative of low levels of bacteremia. These improvements were demonstrated with culture of either Francisella tularensis subsp. tularensis or subsp. holarctica in all examined commercial blood culture types routinely used in a clinical setup. Finally, essential downstream identification assays, such as matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS), immunofluorescence, or antibiotic susceptibility tests, were not affected in the presence of Fe2+. To conclude, supplementing blood cultures with Fe2+ enables a significant shortening of incubation times for F. tularensis diagnosis, without affecting subsequent identification or isolation assays. IMPORTANCE In this study, we evaluated bacterial growth rates of Francisella tularensis strains in iron (Fe)-enriched blood cultures as a means of improving and accelerating bacterial growth. The shortening of the culturing time should facilitate rapid pathogen detection and isolation, positively impacting clinical diagnosis and enabling prompt onset of efficient therapy.
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An Unusual Case of Francisella tularensis. Case Rep Infect Dis 2022; 2022:7250294. [PMID: 35480341 PMCID: PMC9038431 DOI: 10.1155/2022/7250294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 03/27/2022] [Accepted: 04/05/2022] [Indexed: 12/03/2022] Open
Abstract
A 67-year-old male presented with complaints of weakness, fatigue, and shortness of breath in the context of a recent hospitalization for the same unresolved symptoms. After a largely nonspecific clinical presentation, a chest X-ray revealed a loculated pleural effusion. Culture of the postthoracentesis exudate revealed the culprit to be the aerobic Gram-negative bacterium Francisella tularensis. Amidst reports of potential resurgence, clinicians should be aware of the possible presentations of tularemia and consider it in the case of an ostensibly contributory patient history.
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Prah M, Kenk A, Rejc Marko J. Skin involvement in Francisella tularensis infection: a case report of two clinical cases. ACTA DERMATOVENEROLOGICA ALPINA PANNONICA ET ADRIATICA 2022. [DOI: 10.15570/actaapa.2022.13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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8
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Merold V, Silberreis K, Stoecker K. Development and Validation of Ribosomal RNA-Targeted Reverse Transcription Real-Time PCR Assays for the Sensitive and Rapid Diagnostics of High Consequence Pathogens. Front Microbiol 2021; 12:738868. [PMID: 34777285 PMCID: PMC8589101 DOI: 10.3389/fmicb.2021.738868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 09/09/2021] [Indexed: 11/28/2022] Open
Abstract
Real-time PCR (rtPCR) has become an essential tool in clinical microbiology and has been used for the acute diagnostics of many pathogens. Key performance indicators of rtPCR assays are their specificity as well as their analytical and clinical sensitivity. One way to maximize the sensitivity of such diagnostic rtPCRs is the use of genomic targets, which are present in several copies in the target cells. Here, we use the naturally pre-amplified ribosomal RNA as target for specific and highly sensitive reverse-transcription rtPCR detection of two high consequence pathogens, Yersinia pestis and Francisella tularensis. We determined their analytical sensitivity and illustrate that the newly designed assays are superior compared with other previous published rtPCR assays. Furthermore, we used spiked clinical sample matrices to evaluate their clinical applicability. Finally, we demonstrate that these assays can be applied on heat-inactivated samples without the need of time-consuming nucleic acid extraction.
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Tularemia: A rare cause of pediatric lymph nodes adenitis. Arch Pediatr 2021; 28:580-582. [PMID: 34511278 DOI: 10.1016/j.arcped.2021.08.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 05/29/2021] [Accepted: 08/09/2021] [Indexed: 11/23/2022]
Abstract
Adenopathy in pediatrics can have many different causes: infectious, tumoral, and inflammatory. We report the case of an 8-year-old patient with a febrile popliteal ulceration associated with an inflammatory satellite inguinal lymph node adenitis. Serological tests and polymerase chain reaction analyses confirmed the diagnosis of ulceroglandular tularemia. An appropriate antimicrobial therapy led to a full recovery. This case reminds us to consider tularemia as a potential emergent disease in children presenting with subacute to chronic lymphadenopathy and thereby to choose the correct diagnostic tool and appropriate antimicrobial therapy.
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In Vitro Antimicrobial Susceptibilities of Francisella tularensis subsp. holarctica Isolates from Tularemia Outbreaks That Occurred from the End of the 20th Century to the 2020s in Spain. Antibiotics (Basel) 2021; 10:antibiotics10080938. [PMID: 34438988 PMCID: PMC8389022 DOI: 10.3390/antibiotics10080938] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/13/2021] [Accepted: 07/28/2021] [Indexed: 11/17/2022] Open
Abstract
A collection of 177 Francisella tularensis subsp. holarctica clinical isolates (29 from humans and 148 from animals, mainly hares and voles) was gathered from diverse tularemia outbreaks in the Castilla y León region (northwestern Spain) that occurred from the end of the 20th century to the 2020s. Along with four F. tularensis subsp. holarctica reference strains, all of these clinical isolates were tested using a broth microdilution method to determine their susceptibility to 22 antimicrobial agents, including β-lactams, aminoglycosides and one member each of the tetracycline, glycylcycline, quinolone and sulphonamide classes. Many multi-resistance profiles were found among the tested isolates, but especially among those of human origin (all but two isolates showed resistance to at least 13 of 18 antimicrobial agents). Even so, all human isolates were susceptible to gentamicin and tobramycin, while more than 96% of animal isolates were susceptible to these two aminoglycosides. Ciprofloxacin showed activity against more than 92% of animal and human isolates. However, almost 21% of human isolates were resistant to tetracycline, and more than 65% were resistant to tigecycline. Finally, a quite similar activity to other F. tularensis subsp. holarctica isolates collected 20 years earlier in Spain was observed.
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Zhou H, Yang Q, Shen L, Yao Y, Xu J, Ye J, Wu X, Yu Y, Li Z, Zhou J, Yang S. Seawater-Associated Highly Pathogenic Francisella hispaniensis Infections Causing Multiple Organ Failure. Emerg Infect Dis 2021; 26:2424-2428. [PMID: 32946719 PMCID: PMC7510699 DOI: 10.3201/eid2610.190844] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
A rare case of Francisella hispaniensis infection associated with seawater exposure occurred in a deep-sea diving fisherman in Zhejiang, China. He had skin and soft tissue infection that progressed to bacteremia and multiple organ failure. Moxifloxacin treatment cleared the infections, but the patient suffered a sequela of heart damage.
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Finafloxacin Is an Effective Treatment for Inhalational Tularemia and Plague in Mouse Models of Infection. Antimicrob Agents Chemother 2021; 65:AAC.02294-20. [PMID: 33753342 PMCID: PMC8315961 DOI: 10.1128/aac.02294-20] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 03/13/2021] [Indexed: 12/27/2022] Open
Abstract
Infection with aerosolized Francisella tularensis or Yersinia pestis can lead to lethal disease in humans if treatment is not initiated promptly. Finafloxacin is a novel fluoroquinolone which has demonstrated broad-spectrum activity against a range of bacterial species in vitro, in vivo, and in humans, activity which is superior in acidic, infection-relevant conditions. Human-equivalent doses of finafloxacin or ciprofloxacin were delivered at 24 h (representing prophylaxis) or at 72 or 38 h (representing treatment) postchallenge with F. tularensis or Y. pestis, respectively, in BALB/c mouse models. In addition, a short course of therapy (3 days) was compared to a longer course (7 days). Both therapies provided a high level of protection against both infections when administered at 24 h postchallenge, irrespective of the length of the dosing regimen; however, differences were observed when therapy was delayed. A benefit was demonstrated with finafloxacin compared to ciprofloxacin in both models when therapy was delivered later in the infection. These studies suggest that finafloxacin is an effective alternative therapeutic for the prophylaxis and treatment of inhalational infections with F. tularensis or Y. pestis.
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Kassinger SJ, van Hoek ML. Genetic Determinants of Antibiotic Resistance in Francisella. Front Microbiol 2021; 12:644855. [PMID: 34054749 PMCID: PMC8149597 DOI: 10.3389/fmicb.2021.644855] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 03/25/2021] [Indexed: 12/21/2022] Open
Abstract
Tularemia, caused by Francisella tularensis, is endemic to the northern hemisphere. This zoonotic organism has historically been developed into a biological weapon. For this Tier 1, Category A select agent, it is important to expand our understanding of its mechanisms of antibiotic resistance (AMR). Francisella is unlike many Gram-negative organisms in that it does not have significant plasmid mobility, and does not express AMR mechanisms on plasmids; thus plasmid-mediated resistance does not occur naturally. It is possible to artificially introduce plasmids with AMR markers for cloning and gene expression purposes. In this review, we survey both the experimental research on AMR in Francisella and bioinformatic databases which contain genomic and proteomic data. We explore both the genetic determinants of intrinsic AMR and naturally acquired or engineered antimicrobial resistance as well as phenotypic resistance in Francisella. Herein we survey resistance to beta-lactams, monobactams, carbapenems, aminoglycosides, tetracycline, polymyxins, macrolides, rifampin, fosmidomycin, and fluoroquinolones. We also highlight research about the phenotypic AMR difference between planktonic and biofilm Francisella. We discuss newly developed methods of testing antibiotics against Francisella which involve the intracellular nature of Francisella infection and may better reflect the eventual clinical outcomes for new antibiotic compounds. Understanding the genetically encoded determinants of AMR in Francisella is key to optimizing the treatment of patients and potentially developing new antimicrobials for this dangerous intracellular pathogen.
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Affiliation(s)
| | - Monique L. van Hoek
- School of Systems Biology, George Mason University, Manassas, VA, United States
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Cummings JE, Slayden KW, Slayden RA. TPR1, a novel rifampicin derivative, demonstrates efficacy alone and in combination with doxycycline against the NIAID Category A priority pathogen Francisella tularensis. JAC Antimicrob Resist 2021; 3:dlab058. [PMID: 34223120 PMCID: PMC8210291 DOI: 10.1093/jacamr/dlab058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 03/24/2021] [Indexed: 12/25/2022] Open
Abstract
Background Francisella tularensis is a highly virulent and contagious Gram-negative intracellular bacterium that causes the disease tularaemia in mammals and is classified as a Category A priority pathogen. Methods We utilized a systematic analysis of antibacterial potency, extent of dissemination by analysis of bacterial burden in a secondary vital organ, and survival rates to assess the efficacy of a novel rifampicin derivative, TPR1. The efficacy of TPR1 was evaluated alone and in combination with the standard of care drug, doxycycline, against type A F. tularensis Schu S4 using a lethal pulmonary model of infection in mice. Results TPR1 has an MIC value range of 0.125–4 mg/L against reference laboratory strain Schu S4 and a panel of clinical strains. TPR1 alone reduced the bacterial burden in the lungs and spleen at 40 mg/kg and 80 mg/kg, and no antagonism was observed when co-administered with doxycycline. Dosing at 40 mg/kg doxycycline reduced the bacterial burden by 1 log10 cfu in the lungs and 4 log10 cfu in the spleen in comparison to untreated controls. Co-administration of TPR1 and doxycycline demonstrated efficacy upon treatment withdrawal after 4 days of treatment, and 100% survival. Conclusions Significantly, TPR1 demonstrated efficacy when delivered alone and in combination with doxycycline, which provides compelling evidence of a superior treatment strategy that would normally rely on a single chemotherapeutic for efficacy. In addition, this work substantiates the use of rifampicin derivatives as a platform for the development of novel treatments to other bacterial agents in addition to tularaemia.
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Affiliation(s)
- Jason E Cummings
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Keaton W Slayden
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Richard A Slayden
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
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15
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Abalos C, Cutrona A, John J. Lessons Learned From a Young Lady With a Bad Sore Throat. Am J Med 2021; 134:54-56. [PMID: 32505702 DOI: 10.1016/j.amjmed.2020.04.038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 04/15/2020] [Accepted: 04/19/2020] [Indexed: 11/30/2022]
Affiliation(s)
- Charmaine Abalos
- Department of Internal Medicine; Physician Resident 2, Graduate Medical Education in Internal Medical, St. Elizabeth Youngstown Hospital, Youngstown, Ohio; Clinical Instructor of Internal Medicine, Northeast Ohio Medical University, Rootstown.
| | - Anthony Cutrona
- Infectious Disease Specialist, Northeast Ohio Infectious Disease Associates, Youngstown; Professor of Internal Medicine, Northeast Ohio Medical University, Rootstown
| | - Jisha John
- Infectious Disease Specialist, Northeast Ohio Infectious Disease Associates, Youngstown; Assistant Professor of Internal Medicine, Northeast Ohio Medical University, Rootstown
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16
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Aloni-Grinstein R, Shifman O, Gur D, Aftalion M, Rotem S. MAPt: A Rapid Antibiotic Susceptibility Testing for Bacteria in Environmental Samples as a Means for Bioterror Preparedness. Front Microbiol 2020; 11:592194. [PMID: 33224128 PMCID: PMC7674193 DOI: 10.3389/fmicb.2020.592194] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 09/30/2020] [Indexed: 12/24/2022] Open
Abstract
Antibiotic resistance of bio-threat agents holds major concerns especially in light of advances in methods for engineering pathogens with antibiotic resistance. Preparedness means for rapid identification and prompt proper medical treatment are of need to contain the event and prevent morbidity and spreading of the disease by properly treating exposed individuals before symptoms appearance. Herein, we describe a novel, rapid, simple, specific, and sensitive method named Micro-Agar-PCR-test (MAPt), which determines antibiotic susceptibility of bio-terror pathogens, directly from environmental samples, with no need for any prior isolation, quantification, or enrichment steps. As proof of concept, we have used this approach to obtain correct therapeutic antibiotic minimal inhibitory concentration (MIC) values for the Tier-1 select agents, Bacillus anthracis, Yersinia pestis, and Francisella tularensis, spiked in various environmental samples recapitulating potential bioterror scenarios. The method demonstrated efficiency for a broad dynamic range of bacterial concentrations, both for fast-growing as well as slow-growing bacteria and most importantly significantly shortening the time for accurate results from days to a few hours. The MAPt allows us to address bioterror agents-contaminated environmental samples, offering rational targeted prophylactic treatment, before the onset of morbidity in exposed individuals. Hence, MAPt is expected to provide data for decision-making personal for treatment regimens before the onset of symptoms in infected individuals.
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Affiliation(s)
- Ronit Aloni-Grinstein
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Ohad Shifman
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - David Gur
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Moshe Aftalion
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
| | - Shahar Rotem
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research, Ness-Ziona, Israel
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17
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Reuter M, Kruger DH. Approaches to optimize therapeutic bacteriophage and bacteriophage-derived products to combat bacterial infections. Virus Genes 2020; 56:136-149. [PMID: 32036540 PMCID: PMC7223754 DOI: 10.1007/s11262-020-01735-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 01/18/2020] [Indexed: 12/14/2022]
Abstract
The emerging occurrence of antibiotic-resistant bacterial pathogens leads to a recollection of bacteriophage as antimicrobial therapeutics. This article presents a short overview of the clinical phage application including their use in military medicine and discusses the genotypic and phenotypic properties of a potential "ideal" therapeutic phage. We describe current efforts to engineer phage for their improved usability in pathogen treatment. In addition, phage can be applied for pathogen detection, selective drug delivery, vaccine development, or food and surface decontamination. Instead of viable phage, (engineered) phage-derived enzymes, such as polysaccharide depolymerases or peptidoglycan-degrading enzymes, are considered as promising therapeutic candidates. Finally, we briefly summarize the use of phage for the detection and treatment of "Category A priority pathogens".
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Affiliation(s)
- Monika Reuter
- Institute of Virology, Helmut-Ruska-Haus, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117 Berlin, Germany
| | - Detlev H. Kruger
- Institute of Virology, Helmut-Ruska-Haus, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117 Berlin, Germany
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18
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Siebert C, Villers C, Pavlou G, Touquet B, Yakandawala N, Tardieux I, Renesto P. Francisella novicida and F. philomiragia biofilm features conditionning fitness in spring water and in presence of antibiotics. PLoS One 2020; 15:e0228591. [PMID: 32023304 PMCID: PMC7001994 DOI: 10.1371/journal.pone.0228591] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 01/17/2020] [Indexed: 02/07/2023] Open
Abstract
Biofilms are currently considered as a predominant lifestyle of many bacteria in nature. While they promote survival of microbes, biofilms also potentially increase the threats to animal and public health in case of pathogenic species. They not only facilitate bacteria transmission and persistence, but also promote spreading of antibiotic resistance leading to chronic infections. In the case of Francisella tularensis, the causative agent of tularemia, biofilms have remained largely enigmatic. Here, applying live and static confocal microscopy, we report growth and ultrastructural organization of the biofilms formed in vitro by these microorganisms over the early transition from coccobacillary into coccoid shape during biofilm assembly. Using selective dispersing agents, we provided evidence for extracellular DNA (eDNA) being a major and conserved structural component of mature biofilms formed by both F. subsp. novicida and a human clinical isolate of F. philomiragia. We also observed a higher physical robustness of F. novicida biofilm as compared to F. philomiragia one, a feature likely promoted by specific polysaccharides. Further, F. novicida biofilms resisted significantly better to ciprofloxacin than their planktonic counterparts. Importantly, when grown in biofilms, both Francisella species survived longer in cold water as compared to free-living bacteria, a trait possibly associated with a gain in fitness in the natural aquatic environment. Overall, this study provides information on survival of Francisella when embedded with biofilms that should improve both the future management of biofilm-related infections and the design of effective strategies to tackle down the problematic issue of bacteria persistence in aquatic ecosystems.
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Affiliation(s)
| | - Corinne Villers
- TIMC-IMAG UMR 5525-UGA CNRS, Grenoble Cedex 9, France.,Université de Caen Normandie, EA4655 U2RM, Caen, France
| | - Georgios Pavlou
- Institute for Advanced Biosciences (IAB), Team Membrane Dynamics of Parasite-Host Cell Interactions, CNRS UMR 5309, INSERM U1209, Université Grenoble Alpes, Grenoble, France
| | - Bastien Touquet
- Institute for Advanced Biosciences (IAB), Team Membrane Dynamics of Parasite-Host Cell Interactions, CNRS UMR 5309, INSERM U1209, Université Grenoble Alpes, Grenoble, France
| | | | - Isabelle Tardieux
- Institute for Advanced Biosciences (IAB), Team Membrane Dynamics of Parasite-Host Cell Interactions, CNRS UMR 5309, INSERM U1209, Université Grenoble Alpes, Grenoble, France
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19
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Duplantier AJ, Shurtleff AC, Miller C, Chiang CY, Panchal RG, Sunay M. Combating biothreat pathogens: ongoing efforts for countermeasure development and unique challenges. DRUG DISCOVERY TARGETING DRUG-RESISTANT BACTERIA 2020. [PMCID: PMC7258707 DOI: 10.1016/b978-0-12-818480-6.00007-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Research to discover and develop antibacterial and antiviral drugs with potent activity against pathogens of biothreat concern presents unique methodological and process-driven challenges. Herein, we review laboratory approaches for finding new antibodies, antibiotics, and antiviral molecules for pathogens of biothreat concern. Using high-throughput screening techniques, molecules that directly inhibit a pathogen’s entry, replication, or growth can be identified. Alternatively, molecules that target host proteins can be interesting targets for development when countering biothreat pathogens, due to the modulation of the host immune response or targeting proteins that interfere with the pathways required by the pathogen for replication. Monoclonal and cocktail antibody therapies approved by the Food and Drug Administration for countering anthrax and under development for treatment of Ebola virus infection are discussed. A comprehensive tabular review of current in vitro, in vivo, pharmacokinetic and efficacy datasets has been presented for biothreat pathogens of greatest concern. Finally, clinical trials and animal rule or traditional drug approval pathways are also reviewed. Opinions; interpretations; conclusions; and recommendations are those of the authors and are not necessarily endorsed by the US Army.
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20
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Inhibition of Francisella tularensis phagocytosis using a novel anti-LPS scFv antibody fragment. Sci Rep 2019; 9:11418. [PMID: 31388083 PMCID: PMC6684794 DOI: 10.1038/s41598-019-47931-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 07/25/2019] [Indexed: 12/23/2022] Open
Abstract
Francisella tularensis (Ft), the causative agent of lethal tularemia, is classified as a category A biological warfare threat agent. While Ft infection is treatable by antibiotics, many failed antibiotic treatments were reported, highlighting the need for effective new treatments. It has been demonstrated that binding of antibody-coated bacteria to the Fc receptor located on phagocytic cells is a key process needed for efficient protection against Ft. Yet, Ft utilizes the same receptor to enter the phagocytic cells in order to escape the immune system. To address the question whether an anti-Ft LPS antibody lacking the ability to bind the Fc receptor may inhibit the entry of Ft into host cells, a soluble scFv (TL1-scFv) was constructed from an anti Ft-LPS antibody (TL1) that was isolated from an immune single-chain (scFv) phage-display library. Bacterial uptake was assessed upon infection of macrophages with Ft live attenuated strain (LVS) in the presence of either TL1 or TL1-scFv. While incubation of LVS in the presence of TL1 greatly enhanced bacterial uptake, LVS uptake was significantly inhibited in the presence of TL1-scFv. These results prompt further experiments probing the therapeutic efficacy of TL1-scFv, alone or in combination with antibiotic treatment.
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21
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Bachert BA, Biryukov SS, Chua J, Rodriguez SA, Toothman RG, Cote CK, Klimko CP, Hunter M, Shoe JL, Williams JA, Kuehl KA, Biot FV, Bozue JA. A Francisella novicida Mutant, Lacking the Soluble Lytic Transglycosylase Slt, Exhibits Defects in Both Growth and Virulence. Front Microbiol 2019; 10:1343. [PMID: 31258523 PMCID: PMC6587636 DOI: 10.3389/fmicb.2019.01343] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 05/29/2019] [Indexed: 01/28/2023] Open
Abstract
Francisella tularensis is the causative agent of tularemia and has gained recent interest as it poses a significant biothreat risk. F. novicida is commonly used as a laboratory surrogate for tularemia research due to genetic similarity and susceptibility of mice to infection. Currently, there is no FDA-approved tularemia vaccine, and identifying therapeutic targets remains a critical gap in strategies for combating this pathogen. Here, we investigate the soluble lytic transglycosylase or Slt in F. novicida, which belongs to a class of peptidoglycan-modifying enzymes known to be involved in cell division. We assess the role of Slt in biology and virulence of the organism as well as the vaccine potential of the slt mutant. We show that the F. novicida slt mutant has a significant growth defect in acidic pH conditions. Further microscopic analysis revealed significantly altered cell morphology compared to wild-type, including larger cell size, extensive membrane protrusions, and cell clumping and fusion, which was partially restored by growth in neutral pH or genetic complementation. Viability of the mutant was also significantly decreased during growth in acidic medium, but not at neutral pH. Furthermore, the slt mutant exhibited significant attenuation in a murine model of intranasal infection and virulence could be restored by genetic complementation. Moreover, we could protect mice using the slt mutant as a live vaccine strain against challenge with the parent strain; however, we were not able to protect against challenge with the fully virulent F. tularensis Schu S4 strain. These studies demonstrate a critical role for the Slt enzyme in maintaining proper cell division and morphology in acidic conditions, as well as replication and virulence in vivo. Our results suggest that although the current vaccination strategy with F. novicida slt mutant would not protect against Schu S4 challenges, the Slt enzyme could be an ideal target for future therapeutic development.
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Affiliation(s)
- Beth A Bachert
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, MD, United States
| | - Sergei S Biryukov
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, MD, United States
| | - Jennifer Chua
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, MD, United States
| | - Sabrina A Rodriguez
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, MD, United States
| | - Ronald G Toothman
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, MD, United States
| | - Christopher K Cote
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, MD, United States
| | - Christopher P Klimko
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, MD, United States
| | - Melissa Hunter
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, MD, United States
| | - Jennifer L Shoe
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, MD, United States
| | - Janice A Williams
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, MD, United States
| | - Kathleen A Kuehl
- Pathology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, MD, United States
| | - Fabrice V Biot
- Unité de Bactériologie/UMR_MD1, Département de Biologie des Agents Transmissibles, Institut de Recherche Biomédicale des Armées, Brétigny-sur-Orge, France
| | - Joel A Bozue
- Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Frederick, MD, United States
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22
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Garber B, Glauser J. Tick-Borne Illness for Emergency Medicine Providers. CURRENT EMERGENCY AND HOSPITAL MEDICINE REPORTS 2019. [DOI: 10.1007/s40138-019-00187-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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23
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Aminomethyl spectinomycins: a novel antibacterial chemotype for biothreat pathogens. J Antibiot (Tokyo) 2019; 72:693-701. [PMID: 31164713 PMCID: PMC6684479 DOI: 10.1038/s41429-019-0194-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 04/03/2019] [Accepted: 04/22/2019] [Indexed: 01/06/2023]
Abstract
New antibiotics that are active against multi-drug-resistant strains and difficult-to-treat bacterial infections are needed. Synthetic modification of spectinomycin, a bacterial protein synthesis inhibitor, has been shown to increase antibacterial activity compared with spectinomycin. Aminomethyl spectinomycins are active against Gram-negative and Gram-positive bacterial pathogens. In this study, the ability of aminomethyl spectinomycins to treat biothreat pathogens is examined by MIC profiling, synergy testing, and in vivo efficacy experiments. Compound 1950 exhibited potent antibacterial activity against Gram-negative pathogens Brucella spp., Burkholderia mallei, and Francisella tularensis, but showed little to no growth inhibition against Burkholderia pseudomallei, Bacillus anthracis, and Yersinia pestis. Combination testing in checkerboard assays revealed that aminomethyl spectinomycin-antibiotic combinations had mainly an additive effect against the susceptible biodefense pathogens. The in vivo efficacy of compound 1950 was also demonstrated in mice infected with B. mallei (FMH) or F. tularensis (SchuS4). These results suggest that aminomethyl spectinomycins are promising new candidates for development of therapeutics against biodefense bacterial agents.
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24
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Krause C, Schawitzke A, Grunow R, Jacob D, Röcken C, Egberts JH. Seltene Differenzialdiagnose PET-positiver pulmonaler Raumforderungen. Chirurg 2019; 90:493-495. [DOI: 10.1007/s00104-019-0803-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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25
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Barnes KB, Hamblin KA, Richards MI, Laws TR, Vente A, Atkins HS, Harding SV. The Fluoroquinolone Finafloxacin Protects BALB/c Mice Against an Intranasal Infection With Francisella tularensis Strain SchuS4. Front Microbiol 2019; 10:904. [PMID: 31118924 PMCID: PMC6504792 DOI: 10.3389/fmicb.2019.00904] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 04/09/2019] [Indexed: 01/07/2023] Open
Abstract
The efficacy of the novel fluoroquinolone finafloxacin was evaluated as a potential therapeutic in vitro and in vivo, following an intranasal infection of Francisella tularensis strain SchuS4 in BALB/c mice. We demonstrated that short treatment courses of finafloxacin provide high levels of protection, with a single dose resulting in a significant increase in time to death when compared to ciprofloxacin. In addition, following investigation into the window of opportunity for treatment, we have shown that finafloxacin can provided protection when administered up to 96 h post-challenge. This is particularly encouraging since mice displayed severe signs of disease at this time point. In summary, finafloxacin may be a promising therapy for use in the event of exposure to F. tularensis, perhaps enabling the treatment regimen to be shortened or if therapy is delayed. The efficacy of finafloxacin against other biological threat agents also warrants investigation.
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Affiliation(s)
- Kay B Barnes
- Defence Science and Technology Laboratory, Salisbury, United Kingdom
| | | | - Mark I Richards
- Defence Science and Technology Laboratory, Salisbury, United Kingdom
| | - Thomas R Laws
- Defence Science and Technology Laboratory, Salisbury, United Kingdom
| | | | - Helen S Atkins
- Defence Science and Technology Laboratory, Salisbury, United Kingdom.,University of Exeter, Exeter, United Kingdom.,London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Sarah V Harding
- Defence Science and Technology Laboratory, Salisbury, United Kingdom
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26
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Green MS, LeDuc J, Cohen D, Franz DR. Confronting the threat of bioterrorism: realities, challenges, and defensive strategies. THE LANCET. INFECTIOUS DISEASES 2018; 19:e2-e13. [PMID: 30340981 PMCID: PMC7106434 DOI: 10.1016/s1473-3099(18)30298-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 04/25/2018] [Accepted: 05/04/2018] [Indexed: 01/30/2023]
Abstract
Global terrorism is a rapidly growing threat to world security, and increases the risk of bioterrorism. In this Review, we discuss the potential threat of bioterrorism, agents that could be exploited, and recent developments in technologies and policy for detecting and controlling epidemics that have been initiated intentionally. The local and international response to infectious disease epidemics, such as the severe acute respiratory syndrome and west African Ebola virus epidemic, revealed serious shortcomings which bioterrorists might exploit when intentionally initiating an epidemic. Development of new vaccines and antimicrobial therapies remains a priority, including the need to expedite clinical trials using new methodologies. Better means to protect health-care workers operating in dangerous environments are also needed, particularly in areas with poor infrastructure. New and improved approaches should be developed for surveillance, early detection, response, effective isolation of patients, control of the movement of potentially infected people, and risk communication. Access to dangerous pathogens should be appropriately regulated, without reducing progress in the development of countermeasures. We conclude that preparedness for intentional outbreaks has the important added value of strengthening preparedness for natural epidemics, and vice versa.
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Affiliation(s)
- Manfred S Green
- School of Public Health, University of Haifa, Haifa, Israel.
| | - James LeDuc
- Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX, USA
| | - Daniel Cohen
- School of Public Health, Tel Aviv University, Tel Aviv, Israel
| | - David R Franz
- College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
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27
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Avril A. Therapeutic Antibodies for Biodefense. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1053:173-205. [PMID: 29549640 DOI: 10.1007/978-3-319-72077-7_9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Diseases can be caused naturally by biological agents such as bacteria, viruses and toxins (natural risk). However, such biological agents can be intentionally disseminated in the environment by a State (military context) or terrorists to cause diseases in a population or livestock, to destabilize a nation by creating a climate of terror, destabilizing the economy and undermining institutions. Biological agents can be classified according to the severity of illness they cause, its mortality and how easily the agent can be spread. The Centers for Diseases Control and Prevention (CDC) classify biological agents in three categories (A, B and C); Category A consists of the six pathogens most suitable for use as bioweapons (Bacillus anthracis, Yersinia pestis, Francisella tularensis, botulinum neurotoxins, smallpox and viral hemorrhagic fevers). Antibodies represent a perfect biomedical countermeasure as they present both prophylactic and therapeutic properties, act fast and are highly specific to the target. This review focuses on the main biological agents that could be used as bioweapons, the history of biowarfare and antibodies that have been developed to neutralize these agents.
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Affiliation(s)
- Arnaud Avril
- Département des maladies infectieuses, Unité biothérapies anti-infectieuses et immunité, Institut de Recherche Biomédical des Armées, Brétigny-sur-Orge, France.
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28
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Karlı A, Şensoy G, Paksu Ş, Korkmaz MF, Ertuğrul Ö, Karlı R. Treatment-failure tularemia in children. KOREAN JOURNAL OF PEDIATRICS 2018; 61:49-52. [PMID: 29563944 PMCID: PMC5854842 DOI: 10.3345/kjp.2018.61.2.49] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 09/10/2017] [Accepted: 12/15/2017] [Indexed: 01/14/2023]
Abstract
Purpose Tularemia is an infection caused by Francisella tularensis. Its diagnosis and treatment may be difficult in many cases. The aim of this study was to evaluate treatment modalities for pediatric tularemia patients who do not respond to medical treatment. Methods A single-center, retrospective study was performed. A total of 19 children with oropharyngeal tularemia were included. Results Before diagnosis, the duration of symptoms in patients was 32.15±17.8 days. The most common lymph node localization was the cervical chain. All patients received medical treatment (e.g., streptomycin, gentamicin, ciprofloxacin, and doxycycline). Patients who had been given streptomycin, gentamicin, or doxycycline as initial therapy for 10–14 days showed no response to treatment, and recovery was only achieved after administration of oral ciprofloxacin. Response to treatment was delayed in 5 patients who had been given ciprofloxacin as initial therapy. Surgical incision and drainage were performed in 9 patients (47.5%) who were unresponsive to medical treatment and were experiencing abcess formation and suppuration. Five patients (26.3%) underwent total mass excision, and 2 patients (10.5%) underwent fine-needle aspiration to reach a conclusive differential diagnosis and inform treatment. Conclusion The causes of treatment failure in tularemia include delay in effective treatment and the development of suppurating lymph nodes.
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Affiliation(s)
- Arzu Karlı
- Division of Pediatric Infectious Diseases, Ondokuz Mayis University Faculty of Medicine, Samsun, Turkey
| | - Gülnar Şensoy
- Division of Pediatric Infectious Diseases, Ondokuz Mayis University Faculty of Medicine, Samsun, Turkey
| | - Şule Paksu
- Department of Pediatrics, Ondokuz Mayis University Faculty of Medicine, Samsun, Turkey
| | | | - Ömer Ertuğrul
- Department of Pediatrics, Ondokuz Mayis University Faculty of Medicine, Samsun, Turkey
| | - Rıfat Karlı
- Department of Otorhinolaryngology, Ondokuz Mayis University Faculty of Medicine, Samsun, Turkey
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29
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Handler N, Handler M, Rubins A, Rubins S, Septe M, Janniger C, Schwartz R. Milker's nodule: an occupational infection and threat to the immunocompromised. J Eur Acad Dermatol Venereol 2018; 32:537-541. [DOI: 10.1111/jdv.14687] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Accepted: 10/17/2017] [Indexed: 01/30/2023]
Affiliation(s)
- N.S. Handler
- Dermatology Department; New Jersey Medical School; Rutgers University School of Public Affairs and Administration; Newark NJ USA
| | - M.Z. Handler
- Dermatology Department; New Jersey Medical School; Rutgers University School of Public Affairs and Administration; Newark NJ USA
| | - A. Rubins
- Department of Dermatovenerology; Faculty of Medicine; University of Latvia; Riga Latvia
| | - S. Rubins
- Department of Dermatovenerology; Faculty of Medicine; University of Latvia; Riga Latvia
| | - M. Septe
- Department of Dermatovenerology; Faculty of Medicine; University of Latvia; Riga Latvia
| | - C.K. Janniger
- Dermatology Department; New Jersey Medical School; Rutgers University School of Public Affairs and Administration; Newark NJ USA
| | - R.A. Schwartz
- Dermatology Department; New Jersey Medical School; Rutgers University School of Public Affairs and Administration; Newark NJ USA
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30
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Hoang KV, Adcox HE, Fitch JR, Gordon DM, Curry HM, Schlesinger LS, White P, Gunn JS. AR-13, a Celecoxib Derivative, Directly Kills Francisella In Vitro and Aids Clearance and Mouse Survival In Vivo. Front Microbiol 2017; 8:1695. [PMID: 28955308 PMCID: PMC5600997 DOI: 10.3389/fmicb.2017.01695] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 08/23/2017] [Indexed: 12/15/2022] Open
Abstract
Francisella tularensis (F. tularensis) is the causative agent of tularemia and is classified as a Tier 1 select agent. No licensed vaccine is currently available in the United States and treatment of tularemia is confined to few antibiotics. In this study, we demonstrate that AR-13, a derivative of the cyclooxygenase-2 inhibitor celecoxib, exhibits direct in vitro bactericidal killing activity against Francisella including a type A strain of F. tularensis (SchuS4) and the live vaccine strain (LVS), as well as toward the intracellular proliferation of LVS in macrophages, without causing significant host cell toxicity. Identification of an AR-13-resistant isolate indicates that this compound has an intracellular target(s) and that efflux pumps can mediate AR-13 resistance. In the mouse model of tularemia, AR-13 treatment protected 50% of the mice from lethal LVS infection and prolonged survival time from a lethal dose of F. tularensis SchuS4. Combination of AR-13 with a sub-optimal dose of gentamicin protected 60% of F. tularensis SchuS4-infected mice from death. Taken together, these data support the translational potential of AR-13 as a lead compound for the further development of new anti-Francisella agents.
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Affiliation(s)
- Ky V Hoang
- Center for Microbial Interface Biology, Department of Microbial Infection and Immunity, The Ohio State University, ColumbusOH, United States
| | - Haley E Adcox
- Center for Microbial Interface Biology, Department of Microbial Infection and Immunity, The Ohio State University, ColumbusOH, United States
| | - James R Fitch
- The Institute for Genomic Medicine, Nationwide Children's Hospital, ColumbusOH, United States
| | - David M Gordon
- The Institute for Genomic Medicine, Nationwide Children's Hospital, ColumbusOH, United States
| | - Heather M Curry
- Center for Microbial Interface Biology, Department of Microbial Infection and Immunity, The Ohio State University, ColumbusOH, United States
| | - Larry S Schlesinger
- Center for Microbial Interface Biology, Department of Microbial Infection and Immunity, The Ohio State University, ColumbusOH, United States
| | - Peter White
- The Institute for Genomic Medicine, Nationwide Children's Hospital, ColumbusOH, United States.,Department of Pediatrics, The Ohio State University College of Medicine, ColumbusOH, United States
| | - John S Gunn
- Center for Microbial Interface Biology, Department of Microbial Infection and Immunity, The Ohio State University, ColumbusOH, United States
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Benzoxazoles, Phthalazinones, and Arylurea-Based Compounds with IMP Dehydrogenase-Independent Antibacterial Activity against Francisella tularensis. Antimicrob Agents Chemother 2017; 61:AAC.00939-17. [PMID: 28739786 DOI: 10.1128/aac.00939-17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 07/07/2017] [Indexed: 01/06/2023] Open
Abstract
Francisella tularensis is the causative agent of tularemia and a potential biowarfare agent. The virulence of F. tularensis is decreased by deletion of guaB, the gene encoding IMP dehydrogenase (IMPDH), suggesting that this enzyme is a target for antibacterial design. Here we report that F. tularensis growth is blocked by inhibitors of bacterial IMPDHs. Seventeen compounds from two different frameworks, designated the D and Q series, display antibacterial activities with MICs of <1 μM. These compounds are also active against intracellular infections. Surprisingly, antibacterial activity does not correlate with IMPDH inhibition. In addition, the presence of guanine does not affect the antibacterial activity of most compounds, nor does the deletion of guaB These observations suggest that antibacterial activity derives from inhibition of another target(s). Moreover, D compounds display antibacterial activity only against F. tularensis, suggesting the presence of a unique target or uptake mechanism. A ΔguaB mutant resistant to compound D73 contained a missense mutation (Gly45Cys) in nuoB, which encodes a subunit of bacterial complex I. Overexpression of the nuoB mutant conferred resistance to D73 in both wild-type and ΔguaB strains. This strain was not resistant to Q compounds, suggesting that a different off-target mechanism operates for these compounds. Several Q compounds are also effective against Mycobacterium tuberculosis, in which a second target has also been implicated, in addition to IMPDH. The fortuitous presence of multiple targets with overlapping structure-activity relationships presents an intriguing opportunity for the development of robust antibiotics that may avoid the emergence of resistance.
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Ryan DA, Degardin M, Alam S, Kissner TL, Hale M, Cameron MD, Rebek M, Ajami D, Saikh KU, Rebek J. Rational design of peptide derivatives for inhibition of MyD88-mediated toll-like receptor signaling in human peripheral blood mononuclear cells and epithelial cells exposed to Francisella tularensis. Chem Biol Drug Des 2017; 90:1190-1205. [PMID: 28599094 DOI: 10.1111/cbdd.13039] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 05/26/2017] [Accepted: 05/30/2017] [Indexed: 12/17/2022]
Abstract
Small molecules were developed to attenuate proinflammatory cytokines resulting from activation of MyD88-mediated toll-like receptor (TLR) signaling by Francisella tularensis. Fifty-three tripeptide derivatives were synthesized to mimic a key BB-loop region involved in toll-like/interleukin-1 receptor recognition (TIR) domain interactions. Compounds were tested for inhibition of TNF-α, IFN-γ, IL-6, and IL-1β in human peripheral blood mononuclear cells (PBMCs) and primary human bronchial epithelial cells exposed to LPS extracts from F. tularensis. From 53 compounds synthesized and tested, ten compounds were identified as effective inhibitors of F. tularensisLPS-induced cytokines. Compound stability testing in the presence of human liver microsomes and human serum resulted in the identification of tripeptide derivative 7 that was a potent, stable, and drug-like small molecule. Target corroboration using a cell-based reporter assay and competition experiments with MyD88 TIR domain protein supported that the effect of 7 was through MyD88 TIR domain interactions. Compound 7 also attenuated proinflammatory cytokines in human peripheral blood mononuclear cells and bronchial epithelial cells challenged with a live vaccine strain of F. tularensis at a multiplicity of infection of 1:5. Small molecules that target TIR domain interactions in MyD88-dependent TLR signaling represent a promising strategy toward host-directed adjunctive therapeutics for inflammation associated with biothreat agent-induced sepsis.
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Affiliation(s)
- Daniel A Ryan
- Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Melissa Degardin
- Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Shahabuddin Alam
- Department of Immunology, Army Medical Research Institute of Infectious Diseases, Frederick, MD, USA
| | - Teri L Kissner
- Department of Immunology, Army Medical Research Institute of Infectious Diseases, Frederick, MD, USA
| | - Martha Hale
- Department of Immunology, Army Medical Research Institute of Infectious Diseases, Frederick, MD, USA
| | - Michael D Cameron
- Department of Molecular Therapeutics, The Scripps Research Institute, Jupiter, FL, USA
| | - Mitra Rebek
- Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Dariush Ajami
- Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Kamal U Saikh
- Department of Immunology, Army Medical Research Institute of Infectious Diseases, Frederick, MD, USA
| | - Julius Rebek
- Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
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Väyrynen SA, Saarela E, Henry J, Lahti S, Harju T, Kauma H. Pneumonic tularaemia: experience of 58 cases from 2000 to 2012 in Northern Finland. Infect Dis (Lond) 2017; 49:758-764. [PMID: 28618894 DOI: 10.1080/23744235.2017.1341054] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
BACKGROUND Pneumonic tularaemia is less common clinical form of tularaemia compared with the ulceroglandular form, with only a limited number of case reports and case series in Europe. In Finland, Northern Ostrobothnia is an endemic area of tularaemia with occasional seasonal outbreaks. METHODS In our study, a consecutive series of 58 pneumonic tularaemia cases diagnosed and treated in Oulu University Hospital in 2000-2012 were retrospectively analysed in terms of epidemiology, clinical course, and prognosis. RESULTS The incidence of pneumonic tularaemia showed peaks in cycles of a few years and most cases were diagnosed in late summer or early autumn. Respiratory symptoms were absent in 47% of patients, and 7% had normal chest X-ray. The chest computed tomography (CT) was performed in 81% of patients, demonstrating variable findings associated with pneumonic tularaemia. Bronchoscopy was performed for 22 (38%) patients and four (18%) of these also proceeded into mediastinoscopy. Moreover, thoracoscopy was performed for one (2%) patient. Two (3%) patients were treated shortly in the intensive care unit (ICU) during their stay in hospital. No mortality was observed. CONCLUSIONS Most cases of pneumonic tularaemia are diagnosed during the seasonal outbreaks. The lack of specific symptoms often complicates the diagnosis and leads to unnecessarily invasive examinations.
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Affiliation(s)
- Sara A Väyrynen
- a Department of Internal Medicine, Division of Infectious Diseases , Oulu University Hospital and University of Oulu , Oulu , Finland
| | - Elina Saarela
- a Department of Internal Medicine, Division of Infectious Diseases , Oulu University Hospital and University of Oulu , Oulu , Finland
| | - Janne Henry
- b Lammi Health Centre , Hämeenlinna , Finland
| | - Sini Lahti
- c Nordlab Oulu , Oulu University Hospital , Oulu , Finland
| | - Terttu Harju
- d Respiratory Research Unit of Internal Medicine, Medical Research Centre Oulu , Oulu University Hospital and University of Oulu , Oulu , Finland
| | - Heikki Kauma
- a Department of Internal Medicine, Division of Infectious Diseases , Oulu University Hospital and University of Oulu , Oulu , Finland
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Rubins A, Rubins S, Handler NS, Janniger CK, Schwartz RA, Septe M. MILKER’S NODULE. A PERPLEXING FARMYARD INFECTION AND THREAT TO THE IMMUNOCOMPROMISED. VESTNIK DERMATOLOGII I VENEROLOGII 2017. [DOI: 10.25208/0042-4609-2017-93-3-42-52] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Milker’s nodules, also called paravaccinia, is a DNA virus transmitted from infected cows to humans. It results from contact with cattle, cattle byproducts, or fomites. Classified as an occupational disorder, those at risk of exposure include farmers, butchers, and agricultural tourists. The viral infection begins 5—15 days after inoculation as an erythematous-purple, round nodule with a clear depressed center, and a surrounding erythematous ring. While familiar to those in farming communities, the presence of the nodule may be concerning to others, particularly the immunosuppressed. Milker’s nodules are selflimited in immunocompetent individuals and heal without scarring within 8 weeks. Another member of the Parapoxvirus genus, the orf virus, is also transmitted from animals to humans by direct-contact. While complications are rare, hematopoietic stem cell transplant recipients are at risk of graft-versus-host disease, as the parapoxvirus may trigger these complications in immunocompromised individuals. In addition, paravaccinia may serve as the antigen source for the development of erythema multiforme. The unique structure and replication process of viruses in the Poxvirus family, while includes the Parapoxvirus genus, have been a focus for treatment of infections and cancer. Manipulation of these viruses has demonstrated promising therapeutic possibilities as vectors for vaccines and oncologic therapy.
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Functional Characterization of the DNA Gyrases in Fluoroquinolone-Resistant Mutants of Francisella novicida. Antimicrob Agents Chemother 2017; 61:AAC.02277-16. [PMID: 28167561 DOI: 10.1128/aac.02277-16] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 01/20/2017] [Indexed: 11/20/2022] Open
Abstract
Fluoroquinolone (FQ) resistance is a major health concern in the treatment of tularemia. Because DNA gyrase has been described as the main target of these compounds, our aim was to clarify the contributions of both GyrA and GyrB mutations found in Francisella novicida clones highly resistant to FQs. Wild-type and mutated GyrA and GyrB subunits were overexpressed so that the in vitro FQ sensitivity of functional reconstituted complexes could be evaluated. The data obtained were compared to the MICs of FQs against bacterial clones harboring the same mutations and were further validated through complementation experiments and structural modeling. Whole-genome sequencing of highly FQ-resistant lineages was also done. Supercoiling and DNA cleavage assays demonstrated that GyrA D87 is a hot spot FQ resistance target in F. novicida and pointed out the role of the GyrA P43H substitution in resistance acquisition. An unusual feature of FQ resistance acquisition in F. novicida is that the first-step mutation occurs in GyrB, with direct or indirect consequences for FQ sensitivity. Insertion of P466 into GyrB leads to a 50% inhibitory concentration (IC50) comparable to that observed for a mutant gyrase carrying the GyrA D87Y substitution, while the D487E-ΔK488 mutation, while not active on its own, contributes to the high level of resistance that occurs following acquisition of the GyrA D87G substitution in double GyrA/GyrB mutants. The involvement of other putative targets is discussed, including that of a ParE mutation that was found to arise in the very late stage of antibiotic exposure. This study provides the first characterization of the molecular mechanisms responsible for FQ resistance in Francisella.
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Aloni-Grinstein R, Schuster O, Yitzhaki S, Aftalion M, Maoz S, Steinberger-Levy I, Ber R. Isolation of Francisella tularensis and Yersinia pestis from Blood Cultures by Plasma Purification and Immunomagnetic Separation Accelerates Antibiotic Susceptibility Determination. Front Microbiol 2017; 8:312. [PMID: 28293231 PMCID: PMC5329073 DOI: 10.3389/fmicb.2017.00312] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 02/15/2017] [Indexed: 01/16/2023] Open
Abstract
The early symptoms of tularemia and plague, which are caused by Francisella tularensis and Yersinia pestis infection, respectively, are common to other illnesses, resulting in a low index of suspicion among clinicians. Moreover, because these diseases can be treated only with antibiotics, rapid isolation of the bacteria and antibiotic susceptibility testing (AST) are preferable. Blood cultures of patients may serve as a source for bacteria isolation. However, due to the slow growth rates of F. tularensis and Y. pestis on solid media, isolation by plating blood culture samples on proper agar plates may require several days. Thus, improving the isolation procedure prior to antibiotic susceptibility determination is a major clinically relevant need. In this study, we developed a rapid, selective procedure for the isolation of F. tularensis and Y. pestis from blood cultures. We examined drop-plating and plasma purification followed by immunomagnetic separation (IMS) as alternative isolation methods. We determined that replacing the classical isolation method with drop-plating is advantageous with respect to time at the expense of specificity. Hence, we also examined isolation by IMS. Sub-localization of F. tularensis within blood cultures of infected mice has revealed that the majority of the bacteria are located within the extracellular fraction, in the plasma. Y. pestis also resides within the plasma. Therefore, the plasma fraction was isolated from blood cultures and subjected to an IMS procedure using polyclonal anti-F. tularensis live vaccine strain (LVS) or anti-Y. pestis antibodies conjugated to 50-nm nano-beads. The time required to reach an inoculum of sufficient bacteria for AST was shortest when using the plasma and IMSs for both bacteria, saving up to 2 days of incubation for F. tularensis and 1 day for Y. pestis. Our isolation procedure provides a proof of concept for the clinical relevance of rapid isolation for AST from F. tularensis- and Y. pestis-infected patients.
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Affiliation(s)
- Ronit Aloni-Grinstein
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological ResearchNess-Ziona, Israel
| | - Ofir Schuster
- Department of Infectious diseases, Israel Institute for Biological ResearchNess-Ziona, Israel
| | - Shmuel Yitzhaki
- Department of Infectious diseases, Israel Institute for Biological ResearchNess-Ziona, Israel
| | - Moshe Aftalion
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological ResearchNess-Ziona, Israel
| | - Sharon Maoz
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological ResearchNess-Ziona, Israel
| | - Ida Steinberger-Levy
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological ResearchNess-Ziona, Israel
| | - Raphael Ber
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological ResearchNess-Ziona, Israel
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38
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Rojko T, Korva M, Lotrič-Furlan S, Strle F, Avšič-Županc T. Cluster of ulceroglandular tularemia cases in Slovenia. Ticks Tick Borne Dis 2016; 7:1193-1197. [PMID: 27496749 DOI: 10.1016/j.ttbdis.2016.07.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 07/27/2016] [Accepted: 07/29/2016] [Indexed: 11/25/2022]
Abstract
In Slovenia, a small Central European country, where tularemia cases are very rare and mostly sporadic, six cases of ulceroglandular tularemia were recognised in 2012-2013 in patients residing in or visiting a small geographical area of <6km2. Epidemiological data indicated transmission by a tick bite in at least 3/6 patients.
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Affiliation(s)
- Tereza Rojko
- Department of Infectious Diseases, University Medical Centre Ljubljana, Japljeva 2, 1525 Ljubljana, Slovenia.
| | - Miša Korva
- Institute for Microbiology and Immunology, Medical Faculty, University of Ljubljana, Zaloška 4, 1000 Ljubljana, Slovenia
| | - Stanka Lotrič-Furlan
- Department of Infectious Diseases, University Medical Centre Ljubljana, Japljeva 2, 1525 Ljubljana, Slovenia
| | - Franc Strle
- Department of Infectious Diseases, University Medical Centre Ljubljana, Japljeva 2, 1525 Ljubljana, Slovenia
| | - Tatjana Avšič-Županc
- Institute for Microbiology and Immunology, Medical Faculty, University of Ljubljana, Zaloška 4, 1000 Ljubljana, Slovenia
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Maurin M, Gyuranecz M. Tularaemia: clinical aspects in Europe. THE LANCET. INFECTIOUS DISEASES 2016; 16:113-124. [PMID: 26738841 DOI: 10.1016/s1473-3099(15)00355-2] [Citation(s) in RCA: 138] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2014] [Revised: 09/17/2015] [Accepted: 09/21/2015] [Indexed: 10/22/2022]
Abstract
Tularaemia is a zoonotic disease caused by Francisella tularensis, a Gram-negative, facultative intracellular bacterium. Typically, human and animal infections are caused by F tularensis subspecies tularensis (type A) strains mainly in Canada and USA, and F tularensis subspecies holarctica (type B) strains throughout the northern hemisphere, including Europe. In the past, the epidemiological, clinical, therapeutic, and prognostic aspects of tularaemia reported in the English medical literature were mainly those that had been reported in the USA, where the disease was first described. Tularaemia has markedly changed in the past decade, and a large number of studies have provided novel data for the disease characteristics in Europe. In this Review we aim to emphasise the specific and variable aspects of tularaemia in different European countries. In particular, two natural lifecycles of F tularensis have been described in this continent, although not fully characterised, which are associated with different modes of transmission, clinical features, and public health burdens of tularaemia.
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Affiliation(s)
- Max Maurin
- Centre National de Référence des Francisella, Département des Agents Infectieux, Institut de Biologie et Pathologie, CHU de Grenoble, Grenoble, cedex 9, France; Université Grenoble Alpes and Centre National de la Recherche Scientifique, Laboratoire Adaptation et Pathogénie des Microorganismes, IMR 5163, Grenoble, France.
| | - Miklós Gyuranecz
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, Budapest, Hungary; OIE Reference Laboratory for Tularemia, Budapest, Country
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Needle-Free Delivery of Acetalated Dextran-Encapsulated AR-12 Protects Mice from Francisella tularensis Lethal Challenge. Antimicrob Agents Chemother 2016; 60:2052-62. [PMID: 26787696 DOI: 10.1128/aac.02228-15] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 01/06/2016] [Indexed: 11/20/2022] Open
Abstract
Francisella tularensiscauses tularemia and is a potential biothreat. Given the limited antibiotics for treating tularemia and the possible use of antibiotic-resistant strains as a biowarfare agent, new antibacterial agents are needed. AR-12 is an FDA-approved investigational new drug (IND) compound that induces autophagy and has shown host-directed, broad-spectrum activityin vitroagainstSalmonella entericaserovar Typhimurium andF. tularensis We have shown that AR-12 encapsulated within acetalated dextran (Ace-DEX) microparticles (AR-12/MPs) significantly reduces host cell cytotoxicity compared to that with free AR-12, while retaining the ability to controlS.Typhimurium within infected human macrophages. In the present study, the toxicity and efficacy of AR-12/MPs in controlling virulent type AF. tularensisSchuS4 infection were examinedin vitroandin vivo No significant toxicity of blank MPs or AR-12/MPs was observed in lung histology sections when the formulations were given intranasally to uninfected mice. In histology sections from the lungs of intranasally infected mice treated with the formulations, increased macrophage infiltration was observed for AR-12/MPs, with or without suboptimal gentamicin treatment, but not for blank MPs, soluble AR-12, or suboptimal gentamicin alone. AR-12/MPs dramatically reduced the burden ofF. tularensisin infected human macrophages, in a manner similar to that of free AR-12. However,in vivo, AR-12/MPs significantly enhanced the survival ofF. tularensisSchuS4-infected mice compared to that seen with free AR-12. In combination with suboptimal gentamicin treatment, AR-12/MPs further improved the survival ofF. tularensisSchuS4-infected mice. These studies provide support for Ace-DEX-encapsulated AR-12 as a promising new therapeutic agent for tularemia.
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Aloni-Grinstein R, Shifman O, Lazar S, Steinberger-Levy I, Maoz S, Ber R. A rapid real-time quantitative PCR assay to determine the minimal inhibitory extracellular concentration of antibiotics against an intracellular Francisella tularensis Live Vaccine Strain. Front Microbiol 2015; 6:1213. [PMID: 26579112 PMCID: PMC4630301 DOI: 10.3389/fmicb.2015.01213] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 10/19/2015] [Indexed: 12/17/2022] Open
Abstract
Francisella tularensis is a highly virulent facultative intracellular bacterium. The lack of a safe and efficient vaccine makes antibiotics the preferred treatment. F. tularensis antibiotic susceptibility tests are based on the in vitro standard CLSI-approved microdilution method for determining the MIC. However, limited data are available regarding the minimal inhibitory extracellular concentration (MIEC) needed to eradicate intracellular bacteria. Here, we evaluated the MIEC values of various WHO-recommended antibiotics and compared the MIEC values to the established MICs. We describe a rapid 3-h quantitative PCR (qPCR) intracellular antibiogram assay, which yields comparable MIEC values to those obtained by the classical 72-h cfu assay. This rapid qPCR assay is highly advantageous in light of the slow growth rates of F. tularensis. Our results showed that the MIECs obtained for doxycycline, chloramphenicol and ciprofloxacin were indicative of intracellular activity. Gentamicin was not effective against intracellular bacteria for at least 32 h post treatment, raising the question of whether slow-penetrating gentamicin should be used for certain stages of the disease. We suggest that the qPCR intracellular antibiogram assay may be used to screen for potentially active antibiotics against intracellular F. tularensis as well as to detect strains with acquired resistance to recommended antibiotics.
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Affiliation(s)
- Ronit Aloni-Grinstein
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research Ness Ziona, Israel
| | - Ohad Shifman
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research Ness Ziona, Israel
| | - Shlomi Lazar
- Department of Pharmacology, Israel Institute for Biological Research Ness Ziona, Israel
| | - Ida Steinberger-Levy
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research Ness Ziona, Israel
| | - Sharon Maoz
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research Ness Ziona, Israel
| | - Raphael Ber
- Department of Biochemistry and Molecular Genetics, Israel Institute for Biological Research Ness Ziona, Israel
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Abstract
Francisella tularensis is a category A bioterrorism agent. It is the etiological agent of tularemia, a zoonotic disease found throughout the northern hemisphere. The intentional spread of F. tularensis aerosols would probably lead to severe and often fatal pneumonia cases, but also secondary cases from contaminated animals and environments. We are not ready to face such a situation. No vaccine is currently available. A few antibiotics are active against F. tularensis, but strains resistant to these antibiotics could be used in the context of bioterrorism. We need new therapeutic strategies to fight against category A bioterrorism agents, including development of new drugs inhibiting F. tularensis growth and/or virulence, or enhancing the host response to infection by this pathogen.
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Affiliation(s)
- Max Maurin
- Centre National de Référence des Francisella, Département des Agents Infectieux, Institut de Biologie et de Pathologie, CHU de Grenoble, F-38043, Grenoble, France
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43
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Maurin M. New anti-infective strategies for treatment of tularemia. Front Cell Infect Microbiol 2014; 4:115. [PMID: 25191647 PMCID: PMC4137221 DOI: 10.3389/fcimb.2014.00115] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 08/02/2014] [Indexed: 11/13/2022] Open
Affiliation(s)
- Max Maurin
- Centre National de Référence des Francisella, Institut de Biologie et Pathologie, Centre Hospitalier Universitaire de Grenoble Grenoble, France ; Laboratoire Adaptation et Pathogénie des Microorganismes, Université Joseph Fourier - Grenoble 1 Grenoble, France ; Laboratoire Adaptation et Pathogénie des Microorganismes, CNRS/UJF, UMR 5163 Grenoble, France
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