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Alruwaili Y, Jacobs MB, Hasenkampf NR, Tardo AC, McDaniel CE, Embers ME. Superior efficacy of combination antibiotic therapy versus monotherapy in a mouse model of Lyme disease. Front Microbiol 2023; 14:1293300. [PMID: 38075920 PMCID: PMC10703379 DOI: 10.3389/fmicb.2023.1293300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 11/08/2023] [Indexed: 02/08/2024] Open
Abstract
Lyme disease (LD) results from the most prevalent tick-borne infection in North America, with over 476,000 estimated cases annually. The disease is caused by Borrelia burgdorferi (Bb) sensu lato which transmits through the bite of Ixodid ticks. Most cases treated soon after infection are resolved by a short course of oral antibiotics. However, 10-20% of patients experience chronic symptoms because of delayed or incomplete treatment, a condition called Post-Treatment Lyme Disease (PTLD). Some Bb persists in PTLD patients after the initial course of antibiotics and an effective treatment to eradicate the persistent Bb is needed. Other organisms that cause persistent infections, such as M. tuberculosis, are cleared using a combination of therapies rather than monotherapy. A group of Food and Drug Administration (FDA)-approved drugs previously shown to be efficacious against Bb in vitro were used in monotherapy or in combination in mice infected with Bb. Different methods of detection were used to assess the efficacy of the treatments in the infected mice including culture, xenodiagnosis, and molecular techniques. None of the monotherapies eradicated persistent Bb. However, 4 dual combinations (doxycycline + ceftriaxone, dapsone + rifampicin, dapsone + clofazimine, doxycycline + cefotaxime) and 3 triple combinations (doxycycline + ceftriaxone+ carbomycin, doxycycline + cefotaxime+ loratadine, dapsone+ rifampicin+ clofazimine) eradicated persistent Bb infections. These results suggest that combination therapy should be investigated in preclinical studies for treating human Lyme disease.
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Affiliation(s)
- Yasir Alruwaili
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Sakaka, Saudi Arabia
- Division of Immunology, Tulane National Primate Research Center, Tulane University, Covington, LA, United States
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA, United States
| | - Mary B. Jacobs
- Division of Immunology, Tulane National Primate Research Center, Tulane University, Covington, LA, United States
| | - Nicole R. Hasenkampf
- Division of Immunology, Tulane National Primate Research Center, Tulane University, Covington, LA, United States
| | - Amanda C. Tardo
- Division of Immunology, Tulane National Primate Research Center, Tulane University, Covington, LA, United States
| | - Celine E. McDaniel
- Division of Immunology, Tulane National Primate Research Center, Tulane University, Covington, LA, United States
| | - Monica E. Embers
- Division of Immunology, Tulane National Primate Research Center, Tulane University, Covington, LA, United States
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA, United States
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Jacobs MB, Grasperge BJ, Doyle-Meyers LA, Embers ME. Borrelia burgdorferi Migration Assays for Evaluation of Chemoattractants in Tick Saliva. Pathogens 2022; 11:530. [PMID: 35631051 PMCID: PMC9147933 DOI: 10.3390/pathogens11050530] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 04/27/2022] [Accepted: 04/29/2022] [Indexed: 02/04/2023] Open
Abstract
Uptake of the Lyme disease spirochete by its tick vector requires not only chemical signals present in the tick's saliva but a responsive phenotype by the Borrelia burgdorferi living in the mammalian host. This is the principle behind xenodiagnosis, wherein pathogen is detected by vector acquisition. To study migration of B. burgdorferi toward Ixodes scapularis tick saliva, with the goal of identifying chemoattractant molecules, we tested multiple assays and compared migration of host-adapted spirochetes to those cultured in vitro. We tested mammalian host-adapted spirochetes, along with those grown in culture at 34 °C, for their relative attraction to tick saliva or the nutrient N-acetyl-D-glucosamine (D-GlcNAc) and its dimer chitobiose using two different experimental designs. The host-adapted B. burgdorferi showed greater preference for tick saliva over the nutrients, whereas the cultured incubator-grown B. burgdorferi displayed no significant attraction to saliva versus a significant response to the nutrients. Our results not only describe a validated migration assay for studies of the Lyme disease agent, but provide a further understanding of how growth conditions and phenotype of B. burgdorferi are related to vector acquisition.
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Affiliation(s)
- Mary B. Jacobs
- Division of Immunology, Tulane National Primate Research Center, Tulane University Health Sciences, Covington, LA 70433, USA;
| | - Britton J. Grasperge
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70802, USA;
| | - Lara A. Doyle-Meyers
- Division of Veterinary Medicine, Tulane National Primate Research Center, Tulane University Health Sciences, Covington, LA 70433, USA;
| | - Monica E. Embers
- Division of Immunology, Tulane National Primate Research Center, Tulane University Health Sciences, Covington, LA 70433, USA;
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Pflughoeft KJ, Mash M, Hasenkampf NR, Jacobs MB, Tardo AC, Magee DM, Song L, LaBaer J, Philipp MT, Embers ME, AuCoin DP. Multi-platform Approach for Microbial Biomarker Identification Using Borrelia burgdorferi as a Model. Front Cell Infect Microbiol 2019; 9:179. [PMID: 31245298 PMCID: PMC6579940 DOI: 10.3389/fcimb.2019.00179] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 05/09/2019] [Indexed: 01/04/2023] Open
Abstract
The identification of microbial biomarkers is critical for the diagnosis of a disease early during infection. However, the identification of reliable biomarkers is often hampered by a low concentration of microbes or biomarkers within host fluids or tissues. We have outlined a multi-platform strategy to assess microbial biomarkers that can be consistently detected in host samples, using Borrelia burgdorferi, the causative agent of Lyme disease, as an example. Key aspects of the strategy include the selection of a macaque model of human disease, in vivo Microbial Antigen Discovery (InMAD), and proteomic methods that include microbial biomarker enrichment within samples to identify secreted proteins circulating during infection. Using the described strategy, we have identified 6 biomarkers from multiple samples. In addition, the temporal antibody response to select bacterial antigens was mapped. By integrating biomarkers identified from early infection with temporal patterns of expression, the described platform allows for the data driven selection of diagnostic targets.
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Affiliation(s)
- Kathryn J. Pflughoeft
- DxDiscovery, Inc., Reno, NV, United States
- Department of Microbiology and Immunology, Reno School of Medicine, University of Nevada, Reno, NV, United States
| | - Michael Mash
- DxDiscovery, Inc., Reno, NV, United States
- Department of Microbiology and Immunology, Reno School of Medicine, University of Nevada, Reno, NV, United States
| | - Nicole R. Hasenkampf
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA, United States
| | - Mary B. Jacobs
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA, United States
| | - Amanda C. Tardo
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA, United States
| | - D. Mitchell Magee
- Center for Personalized Diagnostics, Biodesign Institute, Arizona State University, Tempe, AZ, United States
| | - Lusheng Song
- Center for Personalized Diagnostics, Biodesign Institute, Arizona State University, Tempe, AZ, United States
| | - Joshua LaBaer
- Center for Personalized Diagnostics, Biodesign Institute, Arizona State University, Tempe, AZ, United States
| | - Mario T. Philipp
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA, United States
| | - Monica E. Embers
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA, United States
| | - David P. AuCoin
- DxDiscovery, Inc., Reno, NV, United States
- Department of Microbiology and Immunology, Reno School of Medicine, University of Nevada, Reno, NV, United States
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Mahdi ES, Bouyssi-Kobar M, Jacobs MB, Murnick J, Chang T, Limperopoulos C. Cerebral Perfusion Is Perturbed by Preterm Birth and Brain Injury. AJNR Am J Neuroradiol 2018; 39:1330-1335. [PMID: 29748205 DOI: 10.3174/ajnr.a5669] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 03/23/2018] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Early disturbances in systemic and cerebral hemodynamics are thought to mediate prematurity-related brain injury. However, the extent to which CBF is perturbed by preterm birth is unknown. Our aim was to compare global and regional CBF in preterm infants with and without brain injury on conventional MR imaging using arterial spin-labeling during the third trimester of ex utero life and to examine the relationship between clinical risk factors and CBF. MATERIALS AND METHODS We prospectively enrolled preterm infants younger than 32 weeks' gestational age and <1500 g and performed arterial spin-labeling MR imaging studies. Global and regional CBF in the cerebral cortex, thalami, pons, and cerebellum was quantified. Preterm infants were stratified into those with and without structural brain injury. We further categorized preterm infants by brain injury severity: moderate-severe and mild. RESULTS We studied 78 preterm infants: 31 without brain injury and 47 with brain injury (29 with mild and 18 with moderate-severe injury). Global CBF showed a borderline significant increase with increasing gestational age at birth (P = .05) and trended lower in preterm infants with brain injury (P = .07). Similarly, regional CBF was significantly lower in the right thalamus and midpons (P < .05) and trended lower in the midtemporal, left thalamus, and anterior vermis regions (P < .1) in preterm infants with brain injury. Regional CBF in preterm infants with moderate-severe brain injury trended lower in the midpons, right cerebellar hemisphere, and dentate nuclei compared with mild brain injury (P < .1). In addition, a significant, lower regional CBF was associated with ventilation, sepsis, and cesarean delivery (P < .05). CONCLUSIONS We report early disturbances in global and regional CBF in preterm infants following brain injury. Regional cerebral perfusion alterations were evident in the thalamus and pons, suggesting regional vulnerability of the developing cerebro-cerebellar circuitry.
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Affiliation(s)
- E S Mahdi
- From the Developing Brain Research Program (E.S.M., M.B.-K., J.M., C.L.), Department of Diagnostic Imaging and Radiology
| | - M Bouyssi-Kobar
- From the Developing Brain Research Program (E.S.M., M.B.-K., J.M., C.L.), Department of Diagnostic Imaging and Radiology
- Department of Neurology (T.C.)
| | - M B Jacobs
- Department of Epidemiology and Biostatistics (M.B.J.), Children's Research Institute, Children's National Health System, Washington, DC
| | - J Murnick
- From the Developing Brain Research Program (E.S.M., M.B.-K., J.M., C.L.), Department of Diagnostic Imaging and Radiology
| | - T Chang
- Department of Neurology (T.C.)
| | - C Limperopoulos
- From the Developing Brain Research Program (E.S.M., M.B.-K., J.M., C.L.), Department of Diagnostic Imaging and Radiology
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Embers ME, Hasenkampf NR, Jacobs MB, Tardo AC, Doyle-Meyers LA, Philipp MT, Hodzic E. Variable manifestations, diverse seroreactivity and post-treatment persistence in non-human primates exposed to Borrelia burgdorferi by tick feeding. PLoS One 2017; 12:e0189071. [PMID: 29236732 PMCID: PMC5728523 DOI: 10.1371/journal.pone.0189071] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 11/17/2017] [Indexed: 01/21/2023] Open
Abstract
The efficacy and accepted regimen of antibiotic treatment for Lyme disease has been a point of significant contention among physicians and patients. While experimental studies in animals have offered evidence of post-treatment persistence of Borrelia burgdorferi, variations in methodology, detection methods and limitations of the models have led to some uncertainty with respect to translation of these results to human infection. With all stages of clinical Lyme disease having previously been described in nonhuman primates, this animal model was selected in order to most closely mimic human infection and response to treatment. Rhesus macaques were inoculated with B. burgdorferi by tick bite and a portion were treated with recommended doses of doxycycline for 28 days at four months post-inoculation. Signs of infection, clinical pathology, and antibody responses to a set of five antigens were monitored throughout the ~1.2 year study. Persistence of B. burgdorferi was evaluated using xenodiagnosis, bioassays in mice, multiple methods of molecular detection, immunostaining with polyclonal and monoclonal antibodies and an in vivo culture system. Our results demonstrate host-dependent signs of infection and variation in antibody responses. In addition, we observed evidence of persistent, intact, metabolically-active B. burgdorferi after antibiotic treatment of disseminated infection and showed that persistence may not be reflected by maintenance of specific antibody production by the host.
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Affiliation(s)
- Monica E. Embers
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA, United States of America
- * E-mail:
| | - Nicole R. Hasenkampf
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA, United States of America
| | - Mary B. Jacobs
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA, United States of America
| | - Amanda C. Tardo
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA, United States of America
| | - Lara A. Doyle-Meyers
- Division of Veterinary Medicine, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA, United States of America
| | - Mario T. Philipp
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA, United States of America
| | - Emir Hodzic
- Center for Comparative Medicine, Schools of Medicine and Veterinary Medicine, University of California Davis, Davis, CA, United States of America
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Martinez AN, Ramesh G, Jacobs MB, Philipp MT. Antagonist of the neurokinin-1 receptor curbs neuroinflammation in ex vivo and in vitro models of Lyme neuroborreliosis. J Neuroinflammation 2015; 12:243. [PMID: 26714480 PMCID: PMC4696197 DOI: 10.1186/s12974-015-0453-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 12/05/2015] [Indexed: 12/31/2022] Open
Abstract
Background Lyme neuroborreliosis (LNB) can affect both the peripheral (PNS) and the central nervous systems (CNS); it is caused by the spirochete Borrelia burgdorferi. The neuropeptide substance P (SP) is an important mediator of both neuroinflammation and blood-brain barrier dysfunction, through its NK1 receptor. Increased levels of SP have been shown to correlate with cell death. The present study used both ex vivo and in vitro models of experimentation to determine if the inflammatory mediator production and concomitant cell death caused by exposure of neural tissues and cells to B. burgdorferi could be attenuated by treatment with a NK1 receptor antagonist. Methods We incubated normal rhesus frontal cortex tissue explants (CNS) and primary cultures of rhesus dorsal root ganglia cells (PNS) with live B. burgdorferi and tested the effectiveness of the NK1 receptor antagonist L703,606 in attenuating inflammatory immune responses and neuronal and glial damage. Culture supernatants and tissue lysates were subjected to multiplex ELISA to quantify immune mediators, while the cells were evaluated for apoptosis by the in situ TUNEL assay. In addition, we identified immune mediators and producer cells in tissue sections by immunofluorescence staining and confocal microscopy. Results Co-incubation of both CNS tissues and PNS cells with the NK1 receptor antagonist attenuated bacterially induced increases in inflammatory cytokine and chemokine production, particularly, IL-6, CXCL8, and CCL2, and reduced apoptosis levels. Confocal microscopy confirmed that neurons and glial cells are sources of these immune mediators. These results suggest that NK1R antagonist treatment is able to reduce downstream pro-inflammatory signaling, thereby indicating that its systemic administration may slow disease progression. Conclusions We propose that SP contributes to neurogenic inflammation in LNB, and provide data to suggest that an NK1 receptor antagonist may represent a novel neuroprotective therapy.
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Affiliation(s)
- Alejandra N Martinez
- Division of Bacteriology & Parasitology, Tulane National Primate Research Center, Covington, LA, USA.
| | - Geeta Ramesh
- Division of Bacteriology & Parasitology, Tulane National Primate Research Center, Covington, LA, USA.
| | - Mary B Jacobs
- Division of Bacteriology & Parasitology, Tulane National Primate Research Center, Covington, LA, USA.
| | - Mario T Philipp
- Division of Bacteriology & Parasitology, Tulane National Primate Research Center, Covington, LA, USA. .,Department of Microbiology and Immunology, Tulane University Medical School, New Orleans, LA, USA.
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Ramesh G, Didier PJ, England JD, Santana-Gould L, Doyle-Meyers LA, Martin DS, Jacobs MB, Philipp MT. Inflammation in the pathogenesis of lyme neuroborreliosis. Am J Pathol 2015; 185:1344-60. [PMID: 25892509 DOI: 10.1016/j.ajpath.2015.01.024] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 01/20/2015] [Accepted: 01/23/2015] [Indexed: 01/03/2023]
Abstract
Lyme neuroborreliosis, caused by the spirochete Borrelia burgdorferi, affects both peripheral and central nervous systems. We assessed a causal role for inflammation in Lyme neuroborreliosis pathogenesis by evaluating the induced inflammatory changes in the central nervous system, spinal nerves, and dorsal root ganglia (DRG) of rhesus macaques that were inoculated intrathecally with live B. burgdorferi and either treated with dexamethasone or meloxicam (anti-inflammatory drugs) or left untreated. ELISA of cerebrospinal fluid showed significantly elevated levels of IL-6, IL-8, chemokine ligand 2, and CXCL13 and pleocytosis in all infected animals, except dexamethasone-treated animals. Cerebrospinal fluid and central nervous system tissues of infected animals were culture positive for B. burgdorferi regardless of treatment. B. burgdorferi antigen was detected in the DRG and dorsal roots by immunofluorescence staining and confocal microscopy. Histopathology revealed leptomeningitis, vasculitis, and focal inflammation in the central nervous system; necrotizing focal myelitis in the cervical spinal cord; radiculitis; neuritis and demyelination in the spinal roots; and inflammation with neurodegeneration in the DRG that was concomitant with significant neuronal and satellite glial cell apoptosis. These changes were absent in the dexamethasone-treated animals. Electromyography revealed persistent abnormalities in F-wave chronodispersion in nerve roots of a few infected animals; which were absent in dexamethasone-treated animals. These results suggest that inflammation has a causal role in the pathogenesis of acute Lyme neuroborreliosis.
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Affiliation(s)
- Geeta Ramesh
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, Louisiana
| | - Peter J Didier
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana
| | - John D England
- Department of Neurology, Louisiana State University Health Sciences Center, New Orleans, Louisiana
| | - Lenay Santana-Gould
- Department of Neurology, Louisiana State University Health Sciences Center, New Orleans, Louisiana
| | - Lara A Doyle-Meyers
- Division of Veterinary Medicine, Tulane National Primate Research Center, Covington, Louisiana
| | - Dale S Martin
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, Louisiana
| | - Mary B Jacobs
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, Louisiana
| | - Mario T Philipp
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, Louisiana.
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Embers ME, Barthold SW, Borda JT, Bowers L, Doyle L, Hodzic E, Jacobs MB, Hasenkampf NR, Martin DS, Narasimhan S, Phillippi-Falkenstein KM, Purcell JE, Ratterree MS, Philipp MT. Correction: Persistence of Borrelia burgdorferi in Rhesus Macaques following Antibiotic Treatment of Disseminated Infection. PLoS One 2013; 8. [PMID: 24116243 PMCID: PMC3792143 DOI: 10.1371/annotation/f84663e3-0a2c-4243-8f97-3a58133c1b0f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
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Embers ME, Grasperge BJ, Jacobs MB, Philipp MT. Feeding of ticks on animals for transmission and xenodiagnosis in Lyme disease research. J Vis Exp 2013. [PMID: 24022694 DOI: 10.3791/50617] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Transmission of the etiologic agent of Lyme disease, Borrelia burgdorferi, occurs by the attachment and blood feeding of Ixodes species ticks on mammalian hosts. In nature, this zoonotic bacterial pathogen may use a variety of reservoir hosts, but the white-footed mouse (Peromyscus leucopus) is the primary reservoir for larval and nymphal ticks in North America. Humans are incidental hosts most frequently infected with B. burgdorferi by the bite of ticks in the nymphal stage. B. burgdorferi adapts to its hosts throughout the enzootic cycle, so the ability to explore the functions of these spirochetes and their effects on mammalian hosts requires the use of tick feeding. In addition, the technique of xenodiagnosis (using the natural vector for detection and recovery of an infectious agent) has been useful in studies of cryptic infection. In order to obtain nymphal ticks that harbor B. burgdorferi, ticks are fed live spirochetes in culture through capillary tubes. Two animal models, mice and nonhuman primates, are most commonly used for Lyme disease studies involving tick feeding. We demonstrate the methods by which these ticks can be fed upon, and recovered from animals for either infection or xenodiagnosis.
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Affiliation(s)
- Monica E Embers
- Division of Bacteriology & Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center
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Embers ME, Barthold SW, Borda JT, Bowers L, Doyle L, Hodzic E, Jacobs MB, Hasenkampf NR, Martin DS, Narasimhan S, Phillippi-Falkenstein KM, Purcell JE, Ratterree MS, Philipp MT. Persistence of Borrelia burgdorferi in rhesus macaques following antibiotic treatment of disseminated infection. PLoS One 2012; 7:e29914. [PMID: 22253822 PMCID: PMC3256191 DOI: 10.1371/journal.pone.0029914] [Citation(s) in RCA: 154] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Accepted: 12/06/2011] [Indexed: 11/30/2022] Open
Abstract
The persistence of symptoms in Lyme disease patients following antibiotic therapy, and their causes, continue to be a matter of intense controversy. The studies presented here explore antibiotic efficacy using nonhuman primates. Rhesus macaques were infected with B. burgdorferi and a portion received aggressive antibiotic therapy 4–6 months later. Multiple methods were utilized for detection of residual organisms, including the feeding of lab-reared ticks on monkeys (xenodiagnosis), culture, immunofluorescence and PCR. Antibody responses to the B. burgdorferi-specific C6 diagnostic peptide were measured longitudinally and declined in all treated animals. B. burgdorferi antigen, DNA and RNA were detected in the tissues of treated animals. Finally, small numbers of intact spirochetes were recovered by xenodiagnosis from treated monkeys. These results demonstrate that B. burgdorferi can withstand antibiotic treatment, administered post-dissemination, in a primate host. Though B. burgdorferi is not known to possess resistance mechanisms and is susceptible to the standard antibiotics (doxycycline, ceftriaxone) in vitro, it appears to become tolerant post-dissemination in the primate host. This finding raises important questions about the pathogenicity of antibiotic-tolerant persisters and whether or not they can contribute to symptoms post-treatment.
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Affiliation(s)
- Monica E. Embers
- Divisions of Bacteriology & Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana, United States of America
- * E-mail: (MEE); (MTP)
| | - Stephen W. Barthold
- Center for Comparative Medicine, Schools of Medicine and Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Juan T. Borda
- Comparative Pathology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana, United States of America
| | - Lisa Bowers
- Divisions of Bacteriology & Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana, United States of America
| | - Lara Doyle
- Veterinary Medicine, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana, United States of America
| | - Emir Hodzic
- Center for Comparative Medicine, Schools of Medicine and Veterinary Medicine, University of California Davis, Davis, California, United States of America
| | - Mary B. Jacobs
- Divisions of Bacteriology & Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana, United States of America
| | - Nicole R. Hasenkampf
- Divisions of Bacteriology & Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana, United States of America
| | - Dale S. Martin
- Divisions of Bacteriology & Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana, United States of America
| | - Sukanya Narasimhan
- Section of Rheumatology, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Kathrine M. Phillippi-Falkenstein
- Veterinary Medicine, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana, United States of America
| | - Jeanette E. Purcell
- Veterinary Medicine, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana, United States of America
| | - Marion S. Ratterree
- Veterinary Medicine, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana, United States of America
| | - Mario T. Philipp
- Divisions of Bacteriology & Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana, United States of America
- * E-mail: (MEE); (MTP)
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Reddie IC, Bhardwaj G, Dauber SL, Jacobs MB, Moran KT. Bilateral retinoschisis in a 2-year-old following a three-storey fall. Eye (Lond) 2010; 24:1426-7. [PMID: 20467447 DOI: 10.1038/eye.2010.70] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Lin T, Gao L, Edmondson DG, Jacobs MB, Philipp MT, Norris SJ. Central role of the Holliday junction helicase RuvAB in vlsE recombination and infectivity of Borrelia burgdorferi. PLoS Pathog 2009; 5:e1000679. [PMID: 19997622 PMCID: PMC2780311 DOI: 10.1371/journal.ppat.1000679] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Accepted: 11/04/2009] [Indexed: 01/11/2023] Open
Abstract
Antigenic variation plays a vital role in the pathogenesis of many infectious bacteria and protozoa including Borrelia burgdorferi, the causative agent of Lyme disease. VlsE, a 35 kDa surface-exposed lipoprotein, undergoes antigenic variation during B. burgdorferi infection of mammalian hosts, and is believed to be a critical mechanism by which the spirochetes evade immune clearance. Random, segmental recombination between the expressed vlsE gene and adjacent vls silent cassettes generates a large number of different VlsE variants within the infected host. Although the occurrence and importance of vlsE sequence variation is well established, little is known about the biological mechanism of vlsE recombination. To identify factors important in antigenic variation and vlsE recombination, we screened transposon mutants of genes known to be involved in DNA recombination and repair for their effects on infectivity and vlsE recombination. Several mutants, including those in BB0023 (ruvA), BB0022 (ruvB), BB0797 (mutS), and BB0098 (mutS-II), showed reduced infectivity in immunocompetent C3H/HeN mice. Mutants in ruvA and ruvB exhibited greatly reduced rates of vlsE recombination in C3H/HeN mice, as determined by restriction fragment polymorphism (RFLP) screening and DNA sequence analysis. In severe combined immunodeficiency (C3H/scid) mice, the ruvA mutant retained full infectivity; however, all recovered clones retained the ‘parental’ vlsE sequence, consistent with low rates of vlsE recombination. These results suggest that the reduced infectivity of ruvA and ruvB mutants is the result of ineffective vlsE recombination and underscores the important role that vlsE recombination plays in immune evasion. Based on functional studies in other organisms, the RuvAB complex of B. burgdorferi may promote branch migration of Holliday junctions during vlsE recombination. Our findings are consistent with those in the accompanying article by Dresser et al., and together these studies provide the first examples of trans-acting factors involved in vlsE recombination. Lyme disease is the most prevalent tick-borne infection in North America and Eurasia. It is caused by the bacterium Borrelia burgdorferi and is transmitted to humans via the bite of infected ticks. These spirochetes can cause both acute and chronic infection and inflammation of the skin, joints, heart, and central nervous system. The persistence of infection despite the presence of an active immune response is dependent upon antigenic variation of VlsE, a 35 kDa surface-exposed lipoprotein. A large number of different VlsE variants are present in the host simultaneously and are generated by recombination of the vlsE gene with adjacent vls silent cassettes. To try to identify factors important in vlsE recombination and immune evasion, we selected mutants in genes involved in DNA recombination and repair and screened them for infectivity and vlsE recombination. Mutants in genes encoding RuvA and RuvB (which act together to promote the exchange of strands between two different DNA molecules) had reduced infectivity and greatly diminished vlsE recombination. In immunodeficient mice, ruvA mutants retained full infectivity, and no vlsE recombination was detected. Our findings reinforce the importance of vlsE variation in immune evasion and persistent infection.
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Affiliation(s)
- Tao Lin
- Department of Pathology and Laboratory Medicine, Medical School, University of Texas Health Science Center at Houston, Houston, Texas, United States of America
| | - Lihui Gao
- Department of Pathology and Laboratory Medicine, Medical School, University of Texas Health Science Center at Houston, Houston, Texas, United States of America
| | - Diane G. Edmondson
- Department of Pathology and Laboratory Medicine, Medical School, University of Texas Health Science Center at Houston, Houston, Texas, United States of America
| | - Mary B. Jacobs
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana, United States of America
| | - Mario T. Philipp
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana, United States of America
| | - Steven J. Norris
- Department of Pathology and Laboratory Medicine, Medical School, University of Texas Health Science Center at Houston, Houston, Texas, United States of America
- Department of Microbiology and Molecular Genetics, Medical School, University of Texas Health Science Center at Houston, Houston, Texas, United States of America
- * E-mail:
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Ramesh G, Borda JT, Gill A, Ribka EP, Morici LA, Mottram P, Martin DS, Jacobs MB, Didier PJ, Philipp MT. Possible role of glial cells in the onset and progression of Lyme neuroborreliosis. J Neuroinflammation 2009; 6:23. [PMID: 19706181 PMCID: PMC2748066 DOI: 10.1186/1742-2094-6-23] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Accepted: 08/25/2009] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Lyme neuroborreliosis (LNB) may present as meningitis, cranial neuropathy, acute radiculoneuropathy or, rarely, as encephalomyelitis. We hypothesized that glia, upon exposure to Borrelia burgdorferi, the Lyme disease agent, produce inflammatory mediators that promote the acute cellular infiltration of early LNB. This inflammatory context could potentiate glial and neuronal apoptosis. METHODS We inoculated live B. burgdorferi into the cisterna magna of rhesus macaques and examined the inflammatory changes induced in the central nervous system (CNS), and dorsal root nerves and ganglia (DRG). RESULTS ELISA of the cerebrospinal fluid (CSF) showed elevated IL-6, IL-8, CCL2, and CXCL13 as early as one week post-inoculation, accompanied by primarily lymphocytic and monocytic pleocytosis. In contrast, onset of the acquired immune response, evidenced by anti-B. burgdorferi C6 serum antibodies, was first detectable after 3 weeks post-inoculation. CSF cell pellets and CNS tissues were culture-positive for B. burgdorferi. Histopathology revealed signs of acute LNB: severe multifocal leptomeningitis, radiculitis, and DRG inflammatory lesions. Immunofluorescence staining and confocal microscopy detected B. burgdorferi antigen in the CNS and DRG. IL-6 was observed in astrocytes and neurons in the spinal cord, and in neurons in the DRG of infected animals. CCL2 and CXCL13 were found in microglia as well as in endothelial cells, macrophages and T cells. Importantly, the DRG of infected animals showed significant satellite cell and neuronal apoptosis. CONCLUSION Our results support the notion that innate responses of glia to B. burgdorferi initiate/mediate the inflammation seen in acute LNB, and show that neuronal apoptosis occurs in this context.
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Affiliation(s)
- Geeta Ramesh
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, LA, USA
| | - Juan T Borda
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA, USA
| | - Amy Gill
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA, USA
| | - Erin P Ribka
- Division of Veterinary Medicine, Tulane National Primate Research Center, Covington, LA, USA
| | - Lisa A Morici
- Department of Microbiology and Immunology, Tulane University Medical School, New Orleans, LA, USA
| | - Peter Mottram
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, LA, USA
| | - Dale S Martin
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, LA, USA
| | - Mary B Jacobs
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, LA, USA
| | - Peter J Didier
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, LA, USA
| | - Mario T Philipp
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, LA, USA
- Department of Microbiology and Immunology, Tulane University Medical School, New Orleans, LA, USA
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Embers ME, Liang FT, Howell JK, Jacobs MB, Purcell JE, Norris SJ, Johnson BJB, Philipp MT. Antigenicity and recombination of VlsE, the antigenic variation protein of Borrelia burgdorferi, in rabbits, a host putatively resistant to long-term infection with this spirochete. ACTA ACUST UNITED AC 2007; 50:421-9. [PMID: 17596185 DOI: 10.1111/j.1574-695x.2007.00276.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Borrelia burgdorferi, the Lyme disease pathogen, employs several immune-evasive strategies to survive in mammals. Unlike mice, major reservoir hosts for B. burgdorferi, rabbits are considered to be nonpermissive hosts for persistent infection. Antigenic variation of the VlsE molecule is a probable evasion strategy known to function in mice. The invariable region 6 (IR6) and carboxyl-terminal domain (Ct) of VlsE elicit dominant antibody responses that are not protective, perhaps to function as decoy epitopes that protect the spirochete. We sought to determine if either of these characteristics of VlsE differed in rabbit infection, contributing to its reputed nonpermissiveness. VlsE recombination was observed in rabbits that were given inoculations with either cultured or host-adapted spirochetes. Early observations showed a lack of anti-C6 (a peptide encompassing the IR6 region) response in most rabbits, so the anti-Ct and anti-C6 responses were monitored for 98 weeks. Anti-C6 antibody appeared as late as 20 weeks postinoculation, and the anti-Ct response, evident within the first 2 weeks, oscillated for prolonged periods of time. These observations, together with the recovery of cultivable spirochetes from tissue of one animal at 98 weeks postinoculation, challenge the notion that the rabbit cannot harbour a long-term B. burgdorferi infection.
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Affiliation(s)
- Monica E Embers
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, LA 70433, USA
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Embers ME, Jacobs MB, Johnson BJB, Philipp MT. Dominant epitopes of the C6 diagnostic peptide of Borrelia burgdorferi are largely inaccessible to antibody on the parent VlsE molecule. Clin Vaccine Immunol 2007; 14:931-6. [PMID: 17567769 PMCID: PMC2044495 DOI: 10.1128/cvi.00075-07] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Lyme borreliosis (LB) is a disease for which antibody-based detection assays are often required for diagnosis. The variable surface molecule VlsE and IR6, one of its invariable regions, are commonly targeted by the antibody response in infected individuals. A series of enzyme-linked immunosorbent assays was performed to comparatively examine the antibody responses of North American LB patients (n = 37) to VlsE and invariable segments of this molecule. Both immunoglobulin M (IgM) and IgG responses to full-length VlsE and to peptides reproducing invariable regions 2, 4, and 6, as well as the invariable domains at the amino and carboxyl termini of VlsE, were assessed. The proportions and specificities of reactivity to the invariable segments were tested by using cognate peptides as competitors for VlsE binding by patient serum antibodies. IR6 epitopes (by the C6 peptide) were found to dominate the response to invariable segments. IR6 (C6)-specific antibodies were detected in 78% of the serum specimens, whereas <40% of patients generated antibodies that bound the N- or C-terminal domain and <12% of patients responded to either IR2 or IR4. Interestingly, 15 of 37 patients generated IgG antibodies that reacted with C6 but not with VlsE. Conversely, IgM responses were frequent for VlsE but not for invariable segments. A representative number of the serum specimens (n = 8) that contained IgG antibodies reacting with both C6 and VlsE was assessed in competition experiments, using C6 as a competitor. Only half of these specimens contained IgG antibodies whose binding to VlsE could be inhibited >50% by competition with the added C6 peptide. The median percent inhibition was 45.5%. These findings indicate that IR6 epitopes are largely concealed from the VlsE molecular surface and that full-length VlsE-based diagnosis likely detects antibodies to conformational and/or variable region epitopes.
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Affiliation(s)
- Monica E Embers
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Health Sciences Center, 18703 Three Rivers Road, Covington, LA 70433, USA.
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Jacobs MB, Norris SJ, Phillippi-Falkenstein KM, Philipp MT. Infectivity of the highly transformable BBE02- lp56- mutant of Borrelia burgdorferi, the Lyme disease spirochete, via ticks. Infect Immun 2006; 74:3678-81. [PMID: 16714602 PMCID: PMC1479252 DOI: 10.1128/iai.00043-06] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Infectious Borrelia burgdorferi strains that have increased transformability with the shuttle vector pBSV2 were recently constructed by inactivating the gene encoding BBE02, a putative restriction-modification gene product expressed by the linear plasmid lp25 (Kawabata et al., Infect. Immun. 72:7147-7154, 2004). The absence of the linear plasmid lp56, which carries another putative restriction-modification gene, further enhanced transformation rates. The infectivity of these mutants was assessed previously in mice that were inoculated with needle and syringe and was found to be equivalent to that of wild-type spirochetes. Here we examined the infectivity of spirochetes to ticks after capillary inoculation of Ixodes scapularis nymphs and the subsequent spirochetal infectivity to mice via ticks by using B. burgdorferi B31 clonal isolates lacking lp56 and/or BBE02. The absence of lp56 (but not BBE02) correlated with a lower number of spirochetes in ticks after feeding on mice; this plasmid thus may play a role, albeit not an essential one, in supporting spirochetal survival in the feeding tick. Importantly, however, the absence of lp56 and BBE02 did not detectably influence infectivity to mice via ticks.
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Affiliation(s)
- Mary B Jacobs
- Division of Bacteriology, Veterinary Medicine, Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana 70433, USA
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Jacobs MB, Purcell JE, Philipp MT. Ixodes scapularis ticks (Acari: Ixodidae) from Louisiana are competent to transmit Borrelia burgdorferi, the agent of Lyme borreliosis. J Med Entomol 2003; 40:964-967. [PMID: 14765677 DOI: 10.1603/0022-2585-40.6.964] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The principal vector of Borrelia burgdorferi, the Lyme borreliosis spirochete, in the Northeast and Midwestern regions of the United States is the blacklegged tick Ixodes scapularis. Because of a favorable environment, I. scapularis is also plentiful in the South; however, a correlation with Lyme borreliosis cases does not exist in this region of the United States. Concern existed that something intrinsic to ticks found in Louisiana could mitigate their ability to transmit B. burgdorferi. Therefore, we set out to assess the ability of I. scapularis ticks from Louisiana to become infected with and transmit B. burgdorferi using mice as hosts. In the laboratory, mating adult female ticks collected in southeastern Louisiana were fed on the ears of rabbits. After oviposition and egg hatching, the resulting larvae were fed on mice that had been needle-inoculated with two different strains of B. burgdorferi sensu stricto, B31 and JD1. Larvae were found to be positive for spirochetes. Additional fed larvae were allowed to molt into the nymphal stage. Flat nymphs remained infected with B. burgdorferi. Infected nymphs were allowed to feed on naïve mice, all of which became infected as shown by culture of ear biopsy specimens. Naïve larvae were then fed on these same mice to assess transmissibility. The resulting engorged larvae harbored spirochetes. We have demonstrated that the I. scapularis ticks found in Louisiana are fully competent to carry and transmit B. burgdorferi infection.
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Affiliation(s)
- Mary B Jacobs
- Division of Bacteriology, Tulane National Primate Research Center, Tulane University Health Sciences Center, 18703 Three Rivers Road, Covington, LA 70433, USA
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Abstract
Borrelia burgdorferi, the Lyme disease spirochete, persistently infects mammalian hosts despite the development of strong humoral responses directed against the pathogen. Here we describe a novel mechanism of immune evasion by B. burgdorferi. In immunocompetent mice, spirochetes that did not express ospC (the outer-surface protein C gene) were selected within 17 d after inoculation, concomitantly with the emergence of anti-OspC antibody. Spirochetes with no detectable OspC transcript that were isolated from immunocompetent mice reexpressed ospC after they were either cultured in vitro or transplanted to naive immunocompetent mice, but not in OspC-immunized mice. B. burgdorferi persistently expressed ospC in severe combined immune-deficient (SCID) mice. Passive immunization of B. burgdorferi-infected SCID mice with an anti-OspC monoclonal antibody selectively eliminated ospC-expressing spirochetes but did not clear the infection. OspC-expressing spirochetes reappeared in SCID mice after the anti-OspC antibody was eliminated. We submit that selection of surface-antigen nonexpressers is an immune evasion mechanism that contributes to spirochetal persistence.
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Affiliation(s)
- Fang Ting Liang
- Department of Parasitology, Tulane Regional Primate Research Center, Tulane University Health Sciences Center, 18703 Three Rivers Road, Covington, LA 70433, USA
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Indest KJ, Howell JK, Jacobs MB, Scholl-Meeker D, Norris SJ, Philipp MT. Analysis of Borrelia burgdorferi vlsE gene expression and recombination in the tick vector. Infect Immun 2001; 69:7083-90. [PMID: 11598084 PMCID: PMC100090 DOI: 10.1128/iai.69.11.7083-7090.2001] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Expression and recombination of the antigenic variation vlsE gene of the Lyme disease spirochete Borrelia burgdorferi were analyzed in the tick vector. To assess vlsE expression, Ixodes scapularis nymphs infected with the B. burgdorferi strain B31 were fed on mice for 48 or 96 h or to repletion and then crushed and acetone fixed either immediately thereafter (ticks collected at the two earlier time points) or 4 days after repletion. Unfed nymphs also were examined. At all of the time points investigated, spirochetes were able to bind a rabbit antibody raised against the conserved invariable region 6 of VlsE, as assessed by indirect immunofluorescence, but not preimmune serum from the same rabbit. This same antibody also bound to B31 spirochetes cultivated in vitro. Intensity of fluorescence appeared highest in cultured spirochetes, followed by spirochetes present in unfed ticks. Only a dim fluorescent signal was observed on spirochetes at the 48 and 96 h time points and at day 4 postrepletion. Expression of vlsE in vitro was affected by a rise in pH from 7.0 to 8.0 at 34 degrees C. Hence, vlsE expression appears to be sensitive to environmental cues of the type found in the B. burgdorferi natural history. To assess vlsE recombination, nymphs were capillary fed the B. burgdorferi B31 clonal isolate 5A3. Ticks thus infected were either left to rest for 4 weeks (Group I) or fed to repletion on a mouse (Group II). The contents of each tick from both groups were cultured and 10 B. burgdorferi clones from the spirochetal isolate of each tick were obtained. The vlsE cassettes from several of these clones were amplified by PCR and sequenced. Regardless of whether the isolate was derived from Group I or Group II ticks, no changes were observed in the vlsE sequence. In contrast, vlsE cassettes amplified from B. burgdorferi clones derived from a mouse that was infected with B31-5A3 capillary-fed nymphs showed considerable recombination. It follows that vlsE recombination does not occur in the tick vector.
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Affiliation(s)
- K J Indest
- Department of Parasitology, Tulane Regional Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana 70433, USA
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Philipp MT, Bowers LC, Fawcett PT, Jacobs MB, Liang FT, Marques AR, Mitchell PD, Purcell JE, Ratterree MS, Straubinger RK. Antibody response to IR6, a conserved immunodominant region of the VlsE lipoprotein, wanes rapidly after antibiotic treatment of Borrelia burgdorferi infection in experimental animals and in humans. J Infect Dis 2001; 184:870-8. [PMID: 11550127 DOI: 10.1086/323392] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2001] [Revised: 06/12/2001] [Indexed: 11/03/2022] Open
Abstract
Invariable region (IR)(6), an immunodominant conserved region of VlsE, the antigenic variation protein of Borrelia burgdorferi, is currently used for the serologic diagnosis of Lyme disease in humans and canines. A longitudinal assessment of anti-IR(6) antibody levels in B. burgdorferi-infected rhesus monkeys revealed that this level diminished sharply after antibiotic treatment (within 25 weeks). In contrast, antibody levels to P39 and to whole-cell antigen extracts of B. burgdorferi either remained unchanged or diminished less. A longitudinal analysis in dogs yielded similar results. In humans, the anti-IR(6) antibody titer diminished by a factor of > or =4 in successfully treated patients and by a factor of <4 in treatment-resistant patients. This result suggests that the quantification of anti-IR(6) antibody titer as a function of time should be investigated further as a test to assess response to Lyme disease therapy or to determine whether a B. burgdorferi infection has been eliminated.
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Affiliation(s)
- M T Philipp
- Tulane Regional Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana 70433, USA.
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Liang FT, Jacobs MB, Philipp MT. C-terminal invariable domain of VlsE may not serve as target for protective immune response against Borrelia burgdorferi. Infect Immun 2001; 69:1337-43. [PMID: 11179296 PMCID: PMC98025 DOI: 10.1128/iai.69.3.1337-1343.2001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
VlsE, the variable surface antigen of the Lyme disease spirochete, Borrelia burgdorferi, contains two invariable domains, at the amino and carboxyl termini, respectively, which collectively account for approximately one-half of the entire molecule's length and remain unchanged during antigenic variation. It is not known if these two invariable domains are exposed at the surface of either the antigen or the spirochete. If they are exposed at the spirochete's surface, they may elicit a protective immune response against B. burgdorferi and serve as vaccine candidates. In this study, a 51-mer synthetic peptide that reproduced the entire sequence of the C-terminal invariable domain of VlsE was conjugated to the carrier keyhole limpet hemocyanin and used to immunize mice. Generated mouse antibody was able to immunoprecipitate native VlsE extracted from cultured B. burgdorferi B31 spirochetes, indicating that the C-terminal invariable domain was exposed at the antigen's surface. However, this domain was inaccessible to antibody binding at the surface of cultured intact spirochetes, as demonstrated by both an immunofluorescence experiment and an in vitro killing assay. Mouse antibody to the C-terminal invariable domain was not able to confer protection against B. burgdorferi infection, indicating that this domain was unlikely exposed at the spirochete's surface in vivo. We concluded that the C-terminal invariable domain was exposed at the antigen's surface but not at the surface of either cultured or in vivo spirochetes and thus cannot elicit protection against B. burgdorferi infection.
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Affiliation(s)
- F T Liang
- Department of Parasitology, Tulane Regional Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana 70433, USA
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Abstract
Clerkship directors have an opportunity to develop consensus on learning objectives for women's health issues and to develop curricula that cross disciplinary boundaries. A collaborative interdisciplinary approach assures proper sequencing of knowledge and skill acquisition, conserves educational resources, and reflects the values of connectedness and patient-centeredness that are central to women's health. The informal networks and the institutional structures that bring clerkship directors together for discussion of a variety of educational issues promote such collaboration. The authors describe three approaches to designing and implementing women's health curricula and discuss how each might be applied to the topic of domestic violence: adding free-standing courses to existing curricula, often as electives; delegating pieces of the women's health curriculum to existing courses; and creating new interdisciplinary curricula that then are integrated into the general curriculum. Each has advantages and disadvantages. Ideally, models for curriculum design will reflect the collaborative patient-centered models upon which the field of women's health is based. Such models enhance program effectiveness by taking advantage of discipline-based expertise while allowing for the sharing of both educational responsibilities and educational resources.
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Affiliation(s)
- D Magrane
- Department of Obstetrics and Gynecology, University of Vermont College of Medicine, Burlington, MA, USA.
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Abstract
The authors describe their year-long collaboration to analyze and integrate the elements of women's health into their medical school's core curriculum in internal medicine for the third-year clerkship. Such a process was necessary because the current curriculum was inadequate in its treatment of women's health (e.g., little or no coverage of issues pertaining to women in teaching about certain disorders; lack of female subjects in many research studies; study designs' using standards derived from manifestations of diseases in men; the cross-discipline aspects of women's health). The authors illustrate the new curriculum by discussing the revised module in pulmonary medicine; they detail the steps they took to uncover problems and omissions in the existing curriculum and in the literature on the topic, and how they remedied these. (For example, in a case involving a man with pulmonary embolus, one of the new questions for students is "What questions would you ask if this patient were a woman?") They comment on the challenges they faced in revising the curriculum, including lack of protected time, lack of sufficient data about women's health, inherent sex and gender bias in the literature and educational materials, need to make students aware of the importance of sex and gender considerations in patient care, and the ingrained bias of faculty, including the authors. Their process can be adapted and used to integrate curricula in other emerging interdisciplinary fields, such as cross-cultural medicine and gay and lesbian health. The authors conclude that collaboration between students and faculty, as illustrated in their own efforts, is one way to ensure that future practitioners are optimally trained to treat patients in the ever-changing field of medicine.
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Affiliation(s)
- J Nicolette
- University of California, Davis, Davis, California, USA
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Fazeli P, Harvell J, Jacobs MB. Osteoma cutis (cutaneous ossification). West J Med 1999; 171:243-5. [PMID: 10578679 PMCID: PMC1305860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Affiliation(s)
- P Fazeli
- Stanford Medical Group, Palo Alto, CA 94304, USA
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Abstract
BACKGROUND Orbital tuberculosis is exceedingly rare in areas where tuberculosis is non-endemic. A case of childhood orbital tuberculosis is reported, which the authors believe to be the first reported case of orbital tuberculosis in the Australasian region. METHODS/RESULTS The patient a 6-year-old boy presented with proptosis and was initially mistaken to have an orbital malignancy. Treatment with antituberculous drugs resulted in resolution of the condition. CONCLUSION This case served as a timely reminder of the need to keep awareness of the extrapulmonary manifestations of tuberculosis alive even in developed countries. A high index of suspicion for this eminently treatable disease in the appropriate clinical situation is particularly important when migrant communities from high-prevalence areas are involved.
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Affiliation(s)
- P K Chin
- Royal Alexandra Hospital for Children, Camperdown, New South Wales, Australia.
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Morton JA, Jacobs MB. A dangerous profession. West J Med 1996; 164:276. [PMID: 8775948 PMCID: PMC1303431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- J A Morton
- Department of Medicine, Stanford University School of Medicine, Palo Alto, California, USA
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Abstract
A piezoelectric (PZ) quartz crystal microbalance (QCM) biosensor for the rapid detection of Vibrio cholerae serotype O139 has been developed. The antibody to this serotype was immobilized on the gold transducer surface of a 10 MHz AT cut PZ crystal. Solutions containing known antigen concentrations were then incubated for 1 h on the antibody-bound transducer. The biosensor was able to detect 10(5) cells per ml of O139 versus a background of O1 (Ogawa) serotype.
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Affiliation(s)
- R M Carter
- Universal Sensors, Inc., Metairie, LA 70006, USA
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Brown MA, Jacobs MB, Pelayo R. Adult obstructive sleep apnea with secondary enuresis. West J Med 1995; 163:478-80. [PMID: 8533419 PMCID: PMC1303181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- M A Brown
- Stanford University Medical Center, Palo Alto, California, USA
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Carter RM, Guilbault GG, Lubrano GJ, Jacobs MB. Additional strategies for improving sensitivity and reliability of immunoassay. Clin Chem 1994; 40:1986-7. [PMID: 7923789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Affiliation(s)
- M B Jacobs
- Section on Primary Care Medicine, Stanford University School of Medicine, CA 94305
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Varon J, Jacobs MB, Mahoney CA. Reflections on the anion gap in hyperglycemia. West J Med 1992; 157:670-2. [PMID: 1475959 PMCID: PMC1022110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- J Varon
- Department of Medicine, Stanford University Medical Center, California
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Jacobs MB, Wasserstein PH. Spontaneous intracranial hypotension. An uncommon and underrecognized cause of headache. West J Med 1991; 155:178-80. [PMID: 1926855 PMCID: PMC1002959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- M B Jacobs
- Department of Medicine, Stanford University Medical Center, California 94305-5235
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Abstract
Parkinson's disease affects thousands of Americans, men and women equally and apparently with little regard to race. Its diagnosis depends largely on repeated clinical observations of representative signs, such as resting tremor, rigidity, bradykinesia, and gait disturbances. Patients progress through stages: Early disease involves only one limb or side and confers minimal disability, but advanced disease restricts patients to full care. Treatment is chosen on the basis of disease stage and patient response. Combination carbidopa-levodopa (Sinemet) is appropriate for any significant degree of disability, and other antiparkinsonian drugs and anticholinergic agents may be used as adjuncts. Electroconvulsive therapy, use of selegiline hydrochloride (Eldepryl), and surgery are still undergoing investigation but may hold promise.
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Affiliation(s)
- J Varon
- Department of Medicine, Stanford University School of Medicine, California
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38
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Abstract
Although breast enlargement in boys and men can cause both psychological and physical distress, the disorder is rarely serious and is readily treatable. Several factors can lead to the estrogenic excess that causes growth of breast tissue. Dr Jacobs describes a patient with gynecomastia related to cirrhosis of the liver who responded promptly to a brief course of tamoxifen citrate therapy.
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Affiliation(s)
- M B Jacobs
- Division of General Internal Medicine, Stanford University School of Medicine, CA 94305-5320
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Jacobs MB, Gieron MA, Martinez CR, Campos A, Wood BP. Radiological case of the month. Basal ganglia injury after cardiopulmonary arrest: clinical and magnetic resonance imaging correlation. Am J Dis Child 1990; 144:937-8. [PMID: 2378344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- M B Jacobs
- Department of Neurology, University of South Florida, Tampa
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Abstract
Primary care physicians need to be aware of iatrogenic disease and its causes. Adverse drug reactions, including drug-drug interactions, and certain diagnostic procedures may lead to iatrogenic complications. Hospitalized patients, especially the elderly, face increased risks of such complications. Physicians who are aware of common adverse reactions to drugs, drug combinations, and medical procedures may be able to help patients avoid unnecessary distress and morbidity.
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Affiliation(s)
- M B Jacobs
- Stanford Medical Group, Stanford University Medical Center, California
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Jacobs MB. Serum creatinine increase associated with amiodarone therapy. N Y State J Med 1987; 87:358-9. [PMID: 3475612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Abstract
Subcutaneous atrophy developed in a 36-year-old woman at the site of a triamcinolone acetonide (Kenalog) injection for subdeltoid bursitis. Occurrence of local atrophy after corticosteroid injection is relatively frequent yet unappreciated. It is more common in young women and girls who are given preparations with a lesser degree of water solubility. Although the condition is often reversible, instances of long-term disfigurement are well documented. This complication of a useful treatment method can be avoided by following a set of precautions for local injection of corticosteroids.
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Jacobs MB. The acquired immunodeficiency syndrome and hypercalcemia. West J Med 1986; 144:469-71. [PMID: 3487172 PMCID: PMC1306675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Jacobs MB, Schneider JA. Medical complications of bulimia: a prospective evaluation. Q J Med 1985; 54:177-82. [PMID: 2580331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Recent increase in the identification and treatment of bulimia, an eating disorder characterised by excessive eating and often accompanied by some form of purging behaviour, has led to an interest in its proper medical evaluation. Although scattered reports describe a multitude of associated medical complications, their true incidence is not known. We describe our experience with 39 consecutive bulimic patients who underwent thorough medical evaluation. Serious disease was rarely encountered although a significant association was found between low body weight and hypokalaemia. Elevated serum amylase values were also noted in 15 of 24 patients (62 per cent). The potential utility of the latter in treating bulimic patients is discussed. A practical approach to the management of these patients is outlined.
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Jacobs MB. Eosinophilic fasciitis, reactive hepatitis, and splenomegaly. Arch Intern Med 1985; 145:162-3. [PMID: 3970632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Eosinophilic fasciitis (EF) is an acute, idiopathic inflammatory disorder often manifested by tender swelling of the extremities after extreme physical exertion. It is usually without visceral complications. I treated a 25-year-old man with EF who had reactive hepatitis and splenomegaly. To my knowledge, the former has never been reported and the latter only once.
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Jacobs MB, Yeager M. Thrombotic and infectious complications of Hickman-Broviac catheters. Arch Intern Med 1984; 144:1597-9. [PMID: 6589978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Hickman-Broviac catheters are often used when long-term venous access is required. Although generally safe, catheter-related thrombosis and infection are two of the most frequent and clinically important complications associated with their use. A 47-year-old woman with breast cancer had a Hickman catheter placed for chemotherapy; subsequently, the superior vena caval syndrome developed due to a large thrombus surrounding the catheter tip. A very low dose of streptokinase successfully lysed this clot within 12 hours. A 60-year-old woman with acute myelogenous leukemia had a Hickman catheter placed to facilitate induction and maintenance chemotherapy. Two episodes of catheter-related Staphylococcus epidermidis sepsis later developed, the first of which cleared without removal of the cannula.
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Jacobs MB, Wilson W. Iron deficiency anemia in a vegetarian runner. JAMA 1984; 252:481-2. [PMID: 6737634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Jacobs MB. Hepatic infarction related to oral contraceptive use. Arch Intern Med 1984; 144:642-3. [PMID: 6703837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The first case of oral contraceptive (OC)-related common hepatic artery thrombosis with subsequent hepatic infarction is reported. Hepatic complications of OC use are enumerated and the clinical manifestation of hepatic infarction is described. Propranolol hydrochloride, because of its effect on liver blood flow, may have contributed to this disease process.
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