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Parker MFL, López-Álvarez M, Alanizi AA, Luu JM, Polvoy I, Sorlin AM, Qin H, Lee S, Rabbitt SJ, Pichardo-González PA, Ordonez AA, Blecha J, Rosenberg OS, Flavell RR, Engel J, Jain SK, Ohliger MA, Wilson DM. Evaluating the Performance of Pathogen-Targeted Positron Emission Tomography Radiotracers in a Rat Model of Vertebral Discitis-Osteomyelitis. J Infect Dis 2023; 228:S281-S290. [PMID: 37788505 PMCID: PMC11009497 DOI: 10.1093/infdis/jiad159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2023] Open
Abstract
BACKGROUND Vertebral discitis-osteomyelitis (VDO) is a devastating infection of the spine that is challenging to distinguish from noninfectious mimics using computed tomography and magnetic resonance imaging. We and others have developed novel metabolism-targeted positron emission tomography (PET) radiotracers for detecting living Staphylococcus aureus and other bacteria in vivo, but their head-to-head performance in a well-validated VDO animal model has not been reported. METHODS We compared the performance of several PET radiotracers in a rat model of VDO. [11C]PABA and [18F]FDS were assessed for their ability to distinguish S aureus, the most common non-tuberculous pathogen VDO, from Escherichia coli. RESULTS In the rat S aureus VDO model, [11C]PABA could detect as few as 103 bacteria and exhibited the highest signal-to-background ratio, with a 20-fold increased signal in VDO compared to uninfected tissues. In a proof-of-concept experiment, detection of bacterial infection and discrimination between S aureus and E coli was possible using a combination of [11C]PABA and [18F]FDS. CONCLUSIONS Our work reveals that several bacteria-targeted PET radiotracers had sufficient signal to background in a rat model of S aureus VDO to be potentially clinically useful. [11C]PABA was the most promising tracer investigated and warrants further investigation in human VDO.
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Affiliation(s)
- Matthew F L Parker
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
- Department of Psychiatry, Renaissance School of Medicine at Stony Brook University, New York
| | - Marina López-Álvarez
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
| | - Aryn A Alanizi
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
| | - Justin M Luu
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
| | - Ilona Polvoy
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
| | - Alexandre M Sorlin
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
| | - Hecong Qin
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
| | - Sanghee Lee
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
| | - Sarah J Rabbitt
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
| | | | - Alvaro A Ordonez
- Center for Infection and Inflammation Imaging Research, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Joseph Blecha
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
| | | | - Robert R Flavell
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
| | - Joanne Engel
- Department of Medicine, University of California, San Francisco
- UCSF Department of Microbiology and Immunology, San Francisco, California
| | - Sanjay K Jain
- Center for Infection and Inflammation Imaging Research, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Michael A Ohliger
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
- Department of Radiology, Zuckerberg San Francisco General Hospital, San Francisco, California
| | - David M Wilson
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
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2
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Complete Genome Sequences of Bioluminescent Staphylococcus aureus Strains Xen31 and Xen36, Derived from Two Clinical Isolates. Microbiol Resour Announc 2023; 12:e0002423. [PMID: 36840571 PMCID: PMC10019319 DOI: 10.1128/mra.00024-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023] Open
Abstract
Here, we report complete genome sequences of two clinical isolates of Staphylococcus aureus, namely, Xen31 and Xen36, which have been genetically modified to express an optimized Photorhabdus luminescens luciferase operon. Xen31 and Xen36 are bioluminescent strains used widely for investigation of bacterial pathogenesis, drug discovery, and development of novel therapies.
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3
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Wei J, Tong K, Wang H, Wen Y, Chen L. Intra-articular versus systemic vancomycin for the treatment of periprosthetic joint infection after debridement and spacer implantation in a rat model. Bone Joint Res 2022; 11:371-385. [PMID: 35708551 PMCID: PMC9233408 DOI: 10.1302/2046-3758.116.bjr-2021-0319.r3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Aims Treatment outcomes for methicillin-resistant Staphylococcus aureus (MRSA) periprosthetic joint infection (PJI) using systemic vancomycin and antibacterial cement spacers during two-stage revision arthroplasty remain unsatisfactory. This study explored the efficacy and safety of intra-articular vancomycin injections for PJI control after debridement and cement spacer implantation in a rat model. Methods Total knee arthroplasty (TKA), MRSA inoculation, debridement, and vancomycin-spacer implantation were performed successively in rats to mimic first-stage PJI during the two-stage revision arthroplasty procedure. Vancomycin was administered intraperitoneally or intra-articularly for two weeks to control the infection after debridement and spacer implantation. Results Rats receiving intra-articular vancomycin showed the best outcomes among the four treatment groups, with negative bacterial cultures, increased weight gain, increased capacity for weightbearing activities, increased residual bone volume preservation, and reduced inflammatory reactions in the joint tissues, indicating MRSA eradication in the knee. The vancomycin-spacer and/or systemic vancomycin failed to eliminate the MRSA infections following a two-week antibiotic course. Serum vancomycin levels did not reach nephrotoxic levels in any group. Mild renal histopathological changes, without changes in serum creatinine levels, were observed in the intraperitoneal vancomycin group compared with the intra-articular vancomycin group, but no changes in hepatic structure or serum alanine aminotransferase or aspartate aminotransferase levels were observed. No local complications were observed, such as sinus tract or non-healing surgical incisions. Conclusion Intra-articular vancomycin injection was effective and safe for PJI control following debridement and spacer implantation in a rat model during two-stage revision arthroplasties, with better outcomes than systemic vancomycin administration. Cite this article: Bone Joint Res 2022;11(6):371–385.
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Affiliation(s)
- Jian Wei
- Department of Joint Surgery and Sports Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China.,Joint Disease Research Center of Wuhan University, Wuhan, China
| | - Kai Tong
- Department of Joint Surgery and Sports Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China.,Joint Disease Research Center of Wuhan University, Wuhan, China
| | - Hui Wang
- Department of Pharmacology, Department of Basic Medicine, Wuhan University, Wuhan, China
| | - Yinxian Wen
- Department of Joint Surgery and Sports Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China.,Joint Disease Research Center of Wuhan University, Wuhan, China
| | - Liaobin Chen
- Department of Joint Surgery and Sports Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China.,Joint Disease Research Center of Wuhan University, Wuhan, China
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4
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Intra-articular vancomycin for the prophylaxis of periprosthetic joint infection caused by methicillin-resistant S. aureus after total knee arthroplasty in a rat model: the dosage, efficacy, and safety. Antimicrob Agents Chemother 2021; 66:e0164121. [PMID: 34807762 DOI: 10.1128/aac.01641-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although intra-articular vancomycin powder (VP) is sometimes applied before the closure of the incision to prevent periprosthetic joint infection (PJI) after joint replacement, the dosage, efficacy and safety remain controversial. This study aimed to explore the dosage, efficacy, and safety of intra-articular VP in the prophylaxis of infection after total knee arthroplasty (TKA) in a rat model. Sixty male rats were randomly divided into five groups after receiving TKA surgery: Control (no antibiotics); systemic vancomycin (SV) (intraperitoneal injection, 88 mg/kg, equal to 1g in a patient weighted 70kg); VP0.5, VP1.0 and VP2.0 (44 mg/kg, 88 mg/kg and 176 mg/kg respectively, intra-articular). All animals were inoculated in the knee with methicillin-resistant S. aureus (MRSA). General status, serum biomarkers, radiology, microbiological assay and histopathological tests were assessed within 14 days post-operatively. Compared with the Control and SV groups, bacterial counts, knee-width, tissue inflammation, and osteolysis were reduced in the VP0.5, VP1.0 and VP2.0 groups, without notable bodyweight loss and incision complications. Among all the VP groups, VP1.0 and VP2.0 groups presented superior outcomes in the knee-width and tissue inflammation than the VP0.5 group. Microbial culture indicated that no MRSA survived in the knee of VP1.0 and VP2.0 groups, while bacteria growth was observed in VP0.5 group. No obvious changes in the structure and functional biomarkers of liver and kidney were observed in both SV and VP groups. Therefore, intra-articular vancomycin powder at the dosage from 88 mg/kg to 176 mg/kg may be effective and safe in preventing PJI induced by methicillin-resistant S. aureus in the rat TKA model.
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5
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Kodama J, Chen H, Zhou T, Kushioka J, Okada R, Tsukazaki H, Tateiwa D, Nakagawa S, Ukon Y, Bal Z, Tian H, Zhao J, Kaito T. Antibacterial efficacy of quaternized chitosan coating on 3D printed titanium cage in rat intervertebral disc space. Spine J 2021; 21:1217-1228. [PMID: 33621666 DOI: 10.1016/j.spinee.2021.02.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 02/17/2021] [Accepted: 02/17/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Infection around intervertebral fusion cages can be intractable because of the avascular nature of the intervertebral disc space. Intervertebral cages with antibacterial effects may be a method by which this complication can be prevented. PURPOSE To investigate the bacterial load on the antibacterial coating cages for spinal interbody fusion STUDY DESIGN: An experimental in vitro and in vivo study. METHODS Based on the micro-computed tomography (CT) data of rat caudal discs, mesh-like titanium (Ti) cages that anatomically fit into the discs were fabricated by three-dimensional (3D) printing. Additionally, an antibacterial coating was applied with quaternized chitosan (hydroxypropyltrimethyl ammonium chloride chitosan, HACC). In vitro release kinetics of the HACC was performed, and the antibacterial performance of the HACC-coated (Ti-HACC) cages (via inhibition zone assay, bacterial adhesion assay, and biofilm formation assay) was evaluated. Then, Ti-HACC- or noncoated (Ti) cages were implanted in the caudal discs of rats with bioluminescent Staphylococcus aureus. Bacterial survival was investigated using an in vivo imaging system (IVIS) on postoperative days 1, 3, and 5. On day 5, the infection-related changes (bone destruction and migration of cages) were assessed using micro-CT, and the healing status of the surgical wounds was also assessed. After the removal of the cages, the quantification of bacteria attached to the cages was obtained by IVIS. Histological evaluation was performed by hematoxylin and eosin staining and TRAP (tartrate-resistant acid phosphatase) staining. RESULTS Release kinetic analysis showed the sustained release of HACC over 3 days from Ti-HACC cages. Antibacterial effects of Ti-HACC cages were demonstrated in all in vitro assays. IVIS evaluation indicated that the in vivo implantation of Ti-HACC cages with S. aureus exhibited better wound healing, less infection-related changes on micro-CT, and reduced bacterial quantity in the extracted cages compared to Ti cages. Histological evaluation demonstrated an increased number of TRAP-positive osteoclasts and severe bone destruction in the rats treated with Ti cages. CONCLUSIONS We developed a novel antibacterial HACC-coated intervertebral cage that exhibited prominent antibacterial efficacy and prevented the structural damage caused by the infection in rat caudal discs. CLINICAL SIGNIFICANCE HACC-coated titanium intervertebral cages may be a promising option for preventing intractable postoperative infection in spinal interbody fusion surgery.
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Affiliation(s)
- Joe Kodama
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Hongfang Chen
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University, School of Medicine, 639 Zhizaoju Road, Shanghai 200011, China
| | - Tangjun Zhou
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University, School of Medicine, 639 Zhizaoju Road, Shanghai 200011, China
| | - Junichi Kushioka
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Rintaro Okada
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Hiroyuki Tsukazaki
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Daisuke Tateiwa
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Shinichi Nakagawa
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yuichiro Ukon
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Zeynep Bal
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Haijun Tian
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University, School of Medicine, 639 Zhizaoju Road, Shanghai 200011, China.
| | - Jie Zhao
- Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University, School of Medicine, 639 Zhizaoju Road, Shanghai 200011, China.
| | - Takashi Kaito
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
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Joyce K, Sakai D, Pandit A. Preclinical models of vertebral osteomyelitis and associated infections: Current models and recommendations for study design. JOR Spine 2021; 4:e1142. [PMID: 34337331 PMCID: PMC8313152 DOI: 10.1002/jsp2.1142] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 01/22/2021] [Accepted: 01/27/2021] [Indexed: 12/17/2022] Open
Abstract
Spine-related infections, such as vertebral osteomyelitis, discitis, or spondylitis, are rare diseases that mostly affect adults, and are usually of hematogenous origin. The incidence of this condition has gradually risen in recent years because of increases in spine-related surgery and hospital-acquired infections, an aging population, and intravenous (IV) drug use. Spine infections are most commonly caused by Staphylococcus aureus, while other systemic infections such as tuberculosis and brucellosis can also cause spondylitis. Various animal models of vertebral osteomyelitis and associated infections have been investigated in mouse, rat, chicken, rabbit, dog, and sheep models by hematogenous and direct inoculation in surgery, each with their strengths and limitations. This review is the first of its kind to concisely analyze the various existing animal models used to reproduce clinically relevant models of infection. Spine-related infection models must address the unique anatomy of the spine, the avascular nature of its structures and tissues and the consequences of tissue destruction such as spinal cord compression. Further investigation is necessary to elucidate the specific mechanisms of host-microbe response to inform antimicrobial therapy and administration techniques in a technically demanding body cavity. Small-animal models are not suitable for large instrumentation, and difficult IV access thwarts antibiotic administration. In contrast, large-animal models can be implanted with clinically relevant instrumentation and are resilient to repeat procedures to study postoperative infection. A canine model of infection offers a unique opportunity to design and investigate antimicrobial treatments through recruitment a rich population of canine patients, presenting with a natural disease that is suitable for randomized trials.
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Affiliation(s)
- Kieran Joyce
- CÚRAM SFI Research Centre for Medical DevicesNational University of IrelandGalwayIreland
- School of MedicineNational University of IrelandGalwayIreland
| | - Daisuke Sakai
- Department of Orthopaedic SurgeryTokai University School of MedicineIseharaJapan
| | - Abhay Pandit
- CÚRAM SFI Research Centre for Medical DevicesNational University of IrelandGalwayIreland
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7
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Parker ML, Luu JM, Schulte B, Huynh TL, Stewart MN, Sriram R, Yu MA, Jivan S, Turnbaugh PJ, Flavell RR, Rosenberg OS, Ohliger MA, Wilson DM. Sensing Living Bacteria in Vivo Using d-Alanine-Derived 11C Radiotracers. ACS CENTRAL SCIENCE 2020; 6:155-165. [PMID: 32123733 PMCID: PMC7047270 DOI: 10.1021/acscentsci.9b00743] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Indexed: 06/05/2023]
Abstract
Incorporation of d-amino acids into peptidoglycan is a unique metabolic feature of bacteria. Since d-amino acids are not metabolic substrates in most mammalian tissues, this difference can be exploited to detect living bacteria in vivo. Given the prevalence of d-alanine in peptidoglycan muropeptides, as well as its role in several antibiotic mechanisms, we targeted this amino acid for positron emission tomography (PET) radiotracer development. d-[3-11C]Alanine and the dipeptide d-[3-11C]alanyl-d-alanine were synthesized via asymmetric alkylation of glycine-derived Schiff-base precursors with [11C]methyl iodide in the presence of a cinchonidinium phase-transfer catalyst. In cell experiments, both tracers showed accumulation by a wide variety of both Gram-positive and Gram-negative pathogens including Staphylococcus aureus and Pseudomonas aeruginosa. In a mouse model of acute bacterial myositis, d-[3-11C]alanine was accumulated by living microorganisms but was not taken up in areas of sterile inflammation. When compared to existing clinical nuclear imaging tools, specifically 2-deoxy-2-[18F]fluoro-d-glucose and a gallium citrate radiotracer, d-alanine showed more bacteria-specific uptake. Decreased d-[3-11C]alanine uptake was also observed in antibiotic-sensitive microbes after antimicrobial therapy, when compared to that in resistant organisms. Finally, prominent uptake of d-[3-11C]alanine uptake was seen in rodent models of discitis-osteomyelitis and P. aeruginosa pneumonia. These data provide strong justification for clinical translation of d-[3-11C]alanine to address a number of important human infections.
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Affiliation(s)
- Matthew
F. L. Parker
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Justin M. Luu
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Brailee Schulte
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Tony L. Huynh
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Megan N. Stewart
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Renuka Sriram
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Michelle A. Yu
- Department
of Medicine, University of California, San
Francisco, San Francisco, California 94158, United States
| | - Salma Jivan
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Peter J. Turnbaugh
- Department
of Microbiology and Immunology, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Robert R. Flavell
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
| | - Oren S. Rosenberg
- Department
of Medicine, University of California, San
Francisco, San Francisco, California 94158, United States
| | - Michael A. Ohliger
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
- Department
of Radiology, Zuckerberg San Francisco General
Hospital, San Francisco, California 94110, United States
| | - David M. Wilson
- Department
of Radiology and Biomedical Imaging, University
of California, San Francisco, San Francisco, California 94158, United States
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8
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Establishment and Initial Testing of a Medium-Sized, Surgically Feasible Animal Model for Brucellar Spondylodiscitis: A Preliminary Study. BIOMED RESEARCH INTERNATIONAL 2019; 2019:7368627. [PMID: 31662995 PMCID: PMC6791230 DOI: 10.1155/2019/7368627] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 08/04/2019] [Accepted: 08/30/2019] [Indexed: 02/06/2023]
Abstract
Brucellar spondylodiscitis, the most prevalent and significant osteoarticular presentation of human Brucellosis, is difficult to diagnose and usually yields irreversible neurologic deficits and spinal deformities. However, no animal models of Brucellar spondylodiscitis exist, allowing for preclinical investigations. The present study investigated whether intraosseous injection of attenuated Brucella melitensis vaccine into rabbits' lumbar vertebrae imitates the radiographic and histopathological characteristics of human Brucellar spondylodiscitis. Radiographic and histopathological analyses at 8 weeks postoperatively revealed radiographic changes within vertebral bodies and intervertebral discs, abscesses formation within the paravertebral soft tissue, and typical prominent inflammation response without caseous necrosis, which were largely comparable to human Brucellar spondylodiscitis. Such a medium-sized, surgically feasible rabbit model provides a promising in vivo setting for further preclinical investigation of Brucellar spondylodiscitis.
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9
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Schlesinger PH, Blair HC, Beer Stolz D, Riazanski V, Ray EC, Tourkova IL, Nelson DJ. Cellular and extracellular matrix of bone, with principles of synthesis and dependency of mineral deposition on cell membrane transport. Am J Physiol Cell Physiol 2019; 318:C111-C124. [PMID: 31532718 DOI: 10.1152/ajpcell.00120.2019] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Bone differs from other connective tissues; it is isolated by a layer of osteoblasts that are connected by tight and gap junctions. This allows bone to create dense lamellar type I collagen, control pH, mineral deposition, and regulate water content forming a compact and strong structure. New woven bone formed after degradation of mineralized cartilage is rapidly degraded and resynthesized to impart structural order for local bone strength. Ossification is regulated by thickness of bone units and by patterning via bone morphogenetic receptors including activin, other bone morphogenetic protein receptors, transforming growth factor-β receptors, all part of a receptor superfamily. This superfamily interacts with receptors for additional signals in bone differentiation. Important features of the osteoblast environment were established using recent tools including osteoblast differentiation in vitro. Osteoblasts deposit matrix protein, over 90% type I collagen, in lamellae with orientation alternating parallel or orthogonal to the main stress axis of the bone. Into this organic matrix, mineral is deposited as hydroxyapatite. Mineral matrix matures from amorphous to crystalline hydroxyapatite. This process includes at least two-phase changes of the calcium-phosphate mineral as well as intermediates involving tropocollagen fibrils to form the bone composite. Beginning with initiation of mineral deposition, there is uncertainty regarding cardinal processes, but the driving force is not merely exceeding the calcium-phosphate solubility product. It occurs behind a epithelial-like layer of osteoblasts, which generate phosphate and remove protons liberated during calcium-phosphate salt deposition. The forming bone matrix is discontinuous from the general extracellular fluid. Required adjustment of ionic concentrations and water removal from bone matrix are important details remaining to be addressed.
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Affiliation(s)
| | - Harry C Blair
- Veterans Affairs Medical Center, Pittsburgh, Pennsylvania.,Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Donna Beer Stolz
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Vladimir Riazanski
- Department of Neurobiology, Pharmacology, and Physiology, University of Chicago, Chicago, Illinois
| | - Evan C Ray
- Renal Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Irina L Tourkova
- Veterans Affairs Medical Center, Pittsburgh, Pennsylvania.,Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Deborah J Nelson
- Department of Neurobiology, Pharmacology, and Physiology, University of Chicago, Chicago, Illinois
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