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Behary J, Raposo AE, Amorim NML, Zheng H, Gong L, McGovern E, Chen J, Liu K, Beretov J, Theocharous C, Jackson MT, Seet-Lee J, McCaughan GW, El-Omar EM, Zekry A. Defining the temporal evolution of gut dysbiosis and inflammatory responses leading to hepatocellular carcinoma in Mdr2 -/- mouse model. BMC Microbiol 2021; 21:113. [PMID: 33858327 PMCID: PMC8048083 DOI: 10.1186/s12866-021-02171-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 03/31/2021] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Emerging evidence implicates the gut microbiome in liver inflammation and hepatocellular carcinoma (HCC) development. We aimed to characterize the temporal evolution of gut dysbiosis, in relation to the phenotype of systemic and hepatic inflammatory responses leading to HCC development. In the present study, Mdr2 -/- mice were used as a model of inflammation-based HCC. Gut microbiome composition and function, in addition to serum LPS, serum cytokines/chemokines and intrahepatic inflammatory genes were measured throughout the course of liver injury until HCC development. RESULTS Early stages of liver injury, inflammation and cirrhosis, were characterized by dysbiosis. Microbiome functional pathways pertaining to gut barrier dysfunction were enriched during the initial phase of liver inflammation and cirrhosis, whilst those supporting lipopolysaccharide (LPS) biosynthesis increased as cirrhosis and HCC ensued. In parallel, serum LPS progressively increased during the course of liver injury, corresponding to a shift towards a systemic Th1/Th17 proinflammatory phenotype. Alongside, the intrahepatic inflammatory gene profile transitioned from a proinflammatory phenotype in the initial phases of liver injury to an immunosuppressed one in HCC. In established HCC, a switch in microbiome function from carbohydrate to amino acid metabolism occurred. CONCLUSION In Mdr2 -/- mice, dysbiosis precedes HCC development, with temporal evolution of microbiome function to support gut barrier dysfunction, LPS biosynthesis, and redirection of energy source utilization. A corresponding shift in systemic and intrahepatic inflammatory responses occurred supporting HCC development. These findings support the notion that gut based therapeutic interventions could be beneficial early in the course of liver disease to halt HCC development.
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Affiliation(s)
- J Behary
- St George and Sutherland Clinical School, UNSW, Sydney, Australia
- Microbiome Research Centre, St George and Sutherland Clinical School, UNSW, Sydney, Australia
- Department of Gastroenterology and Hepatology, St George Hospital, Sydney, Australia
| | - A E Raposo
- St George and Sutherland Clinical School, UNSW, Sydney, Australia
- Microbiome Research Centre, St George and Sutherland Clinical School, UNSW, Sydney, Australia
| | - N M L Amorim
- St George and Sutherland Clinical School, UNSW, Sydney, Australia
- Microbiome Research Centre, St George and Sutherland Clinical School, UNSW, Sydney, Australia
| | - H Zheng
- St George and Sutherland Clinical School, UNSW, Sydney, Australia
- Microbiome Research Centre, St George and Sutherland Clinical School, UNSW, Sydney, Australia
| | - L Gong
- St George and Sutherland Clinical School, UNSW, Sydney, Australia
- Microbiome Research Centre, St George and Sutherland Clinical School, UNSW, Sydney, Australia
| | - E McGovern
- St George and Sutherland Clinical School, UNSW, Sydney, Australia
- Microbiome Research Centre, St George and Sutherland Clinical School, UNSW, Sydney, Australia
| | - J Chen
- Liver Injury and Cancer, Centenary Institute, University of Sydney, Sydney, Australia
| | - K Liu
- Liver Injury and Cancer, Centenary Institute, University of Sydney, Sydney, Australia
- AW Morrow Gastroenterology and Liver Centre, Royal Prince Alfred Hospital, Sydney, Australia
| | - J Beretov
- St George and Sutherland Clinical School, UNSW, Sydney, Australia
- Department of Anatomical Pathology, St George Hospital, Sydney, Australia
| | - C Theocharous
- Department of Anatomical Pathology, St George Hospital, Sydney, Australia
| | - M T Jackson
- St George and Sutherland Clinical School, UNSW, Sydney, Australia
- Microbiome Research Centre, St George and Sutherland Clinical School, UNSW, Sydney, Australia
| | - J Seet-Lee
- St George and Sutherland Clinical School, UNSW, Sydney, Australia
- Microbiome Research Centre, St George and Sutherland Clinical School, UNSW, Sydney, Australia
| | - G W McCaughan
- Liver Injury and Cancer, Centenary Institute, University of Sydney, Sydney, Australia
- AW Morrow Gastroenterology and Liver Centre, Royal Prince Alfred Hospital, Sydney, Australia
| | - E M El-Omar
- St George and Sutherland Clinical School, UNSW, Sydney, Australia
- Microbiome Research Centre, St George and Sutherland Clinical School, UNSW, Sydney, Australia
- Department of Gastroenterology and Hepatology, St George Hospital, Sydney, Australia
| | - A Zekry
- St George and Sutherland Clinical School, UNSW, Sydney, Australia.
- Microbiome Research Centre, St George and Sutherland Clinical School, UNSW, Sydney, Australia.
- Department of Gastroenterology and Hepatology, St George Hospital, Sydney, Australia.
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El-Hoss J, Kolind M, Jackson MT, Deo N, Mikulec K, McDonald MM, Little CB, Little DG, Schindeler A. Modulation of endochondral ossification by MEK inhibitors PD0325901 and AZD6244 (Selumetinib). Bone 2014; 59:151-61. [PMID: 24269278 DOI: 10.1016/j.bone.2013.11.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 11/06/2013] [Accepted: 11/15/2013] [Indexed: 01/19/2023]
Abstract
MEK inhibitors (MEKi) PD0325901 and AZD6244 (Selumetinib) are drugs currently under clinical investigation for cancer treatment, however the Ras-MAPK pathway is also an important mediator of normal bone cell differentiation and function. In this study we examined the effects of these compounds on endochondral processes using both in vitro and in vivo models. Treatment with PD0325901 or AZD6244 significantly increased Runx2 and Alkaline phosphate gene expression in calvarial osteoblasts and decreased TRAP+ cells in induced osteoclast cultures. To test the effects of these drugs on bone healing, C57/Bl6 mice underwent a closed tibial fracture and were treated with PD0325901 or AZD6244 at 10mg/kg/day. Animals were culled at day 10 and at day 21 post-fracture for analysis of the fracture callus and the femoral growth plate in the contralateral leg. MEKi treatment markedly increased cartilage volume in the soft callus at day 10 post-fracture (+60% PD0325901, +20% AZD6244) and continued treatment led to a delay in cartilage remodeling. At the growth plate, we observed an increase in the height of the hypertrophic zone relative to the proliferative zone of +78% in PD0325901 treated mice. Osteoclast surface was significantly decreased both at the terminal end of the growth plate and within the fracture calluses of MEKi treated animals. The mechanistic effects of MEKi on genes encoding cartilage matrix proteins and catabolic enzymes were examined in articular chondrocyte cultures. PD0325901 or AZD6244 led to increased matrix protein expression (Col2a1 and Acan) and decreased expression of catabolic factors (Mmp13 and Adamts-5). Taken together, these data support the hypothesis that MEKi treatment can impact chondrocyte hypertrophy, matrix resorption, and fracture healing. These compounds can also affect bone architecture by expanding the hypertrophic zone of the growth plate and reducing osteoclast surface systemically.
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Affiliation(s)
- J El-Hoss
- Orthopaedic Research & Biotechnology Unit, The Children's Hospital at Westmead, Sydney, Australia; Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, Australia
| | - M Kolind
- Orthopaedic Research & Biotechnology Unit, The Children's Hospital at Westmead, Sydney, Australia
| | - M T Jackson
- Raymond Purves Bone and Joint Research Laboratories, Kolling Institute of Medical Research, University of Sydney, Royal North Shore Hospital, Sydney, Australia
| | - N Deo
- Orthopaedic Research & Biotechnology Unit, The Children's Hospital at Westmead, Sydney, Australia; Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, Australia
| | - K Mikulec
- Orthopaedic Research & Biotechnology Unit, The Children's Hospital at Westmead, Sydney, Australia
| | - M M McDonald
- Bone Biology Group, Garvan Institute for Medical Research, Sydney, Australia
| | - C B Little
- Raymond Purves Bone and Joint Research Laboratories, Kolling Institute of Medical Research, University of Sydney, Royal North Shore Hospital, Sydney, Australia
| | - D G Little
- Orthopaedic Research & Biotechnology Unit, The Children's Hospital at Westmead, Sydney, Australia; Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, Australia
| | - A Schindeler
- Orthopaedic Research & Biotechnology Unit, The Children's Hospital at Westmead, Sydney, Australia; Discipline of Paediatrics and Child Health, Faculty of Medicine, University of Sydney, Sydney, Australia.
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Chan BY, Fuller ES, Russell AK, Smith SM, Smith MM, Jackson MT, Cake MA, Read RA, Bateman JF, Sambrook PN, Little CB. Increased chondrocyte sclerostin may protect against cartilage degradation in osteoarthritis. Osteoarthritis Cartilage 2011; 19:874-85. [PMID: 21619935 DOI: 10.1016/j.joca.2011.04.014] [Citation(s) in RCA: 152] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 04/12/2011] [Accepted: 04/20/2011] [Indexed: 02/02/2023]
Abstract
OBJECTIVES To investigate the regulation of sclerostin (SOST) in osteoarthritis (OA) and its potential effects on articular cartilage degradation. METHODS SOST and other Wnt-β-catenin components were immuno-localised in osteochondral sections of surgically-induced OA in knees of sheep and mice, and human OA samples obtained at arthroplasty. Regulation of SOST mRNA and protein expression by ovine chondrocytes in response to interleukin-1α (IL-1α) or tumour necrosis factor-α (TNFα) was examined in explant cultures. The effect of 25 or 250 ng/ml recombinant SOST alone or in combination with IL-1α, on ovine articular cartilage explant aggrecan degradation, and chondrocyte gene expression of Wnt-β-catenin pathway proteins, metalloproteinases and their inhibitors, and cartilage matrix proteins was quantified. RESULTS Contrary to being an osteocyte-specific protein, SOST was expressed by articular chondrocytes, and mRNA levels were upregulated in vitro by IL-1α but not TNFα. Chondrocyte SOST staining was significantly increased only in the focal area of cartilage damage in surgically-induced OA in sheep and mice, as well as end-stage human OA. In contrast, osteocyte SOST was focally decreased in the subchondral bone in sheep OA in association with bone sclerosis. SOST was biologically active in chondrocytes, inhibiting Wnt-β-catenin signalling and catabolic metalloproteinase [matrix metalloproteinases (MMP) and distintegrin and metalloproteinase with thrombospndin repeats (ADAMTS)] expression, but also decreasing mRNA levels of aggrecan, collagen II and tissue inhibitors of metalloproteinaes (TIMPs). Despite this mixed effect, SOST dose-dependently inhibited IL-1α-stimulated cartilage aggrecanolysis in vitro. CONCLUSIONS These results implicate SOST in regulating the OA disease processes, but suggest opposing effects by promoting disease-associated subchondral bone sclerosis while inhibiting degradation of cartilage.
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Affiliation(s)
- B Y Chan
- Raymond Purves Bone and Joint Research Labs, Kolling Institute of Medical Research, Institute of Bone and Joint Research, University of Sydney, Royal North Shore Hospital, St Leonards, NSW 2065, Australia
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Jackson MT, Prichard HM, Sampson J. Platinum-group elements in sewage sludge and incinerator ash in the United Kingdom: assessment of PGE sources and mobility in cities. Sci Total Environ 2010; 408:1276-1285. [PMID: 19878972 DOI: 10.1016/j.scitotenv.2009.09.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Revised: 08/04/2009] [Accepted: 09/14/2009] [Indexed: 05/28/2023]
Abstract
Platinum-group element (PGE) concentrations in sewage sludge and incinerator ash compared with average PGE concentrations in road dust show a common pattern, characterized by a negative Rh anomaly. This similarity, found at 9 UK incinerators, suggests that there is a universal characteristic PGE pattern produced by common processes of dispersal of Pt, Pd and Rh derived from automobile catalytic converters. Ninety-one sewage sludge and incinerator ash samples from the sewage treatment facilities in Sheffield, Birmingham and 7 other UK cities were analyzed for PGE. The highest concentrations are 602ppb Pt and 710ppb Pd with lower maximum concentrations of 65ppb Rh, 100ppb Ru, 33ppb Ir and 12ppb Os. Ash from incinerated sewage was found to have higher PGE concentrations compared to the original sludge and the PGE ratios are preserved during incineration. Rh is more mobilized and dispersed than the other PGE as it is transported from roads into the drainage system and into sewage. Pt/Pd ratios of 1.0 in road dust and 0.9 in sewage and incinerator ash suggest that Pd is more mobile than Pt during dispersal. PGE abundances in stored incinerator ash of varying ages appear to have been affected by the variation in use of Pt, Pd and Rh in catalytic converters due to variation in their market prices. Concentrations of Os, Ir and Ru in ashes are greater in Sheffield and London than all the other city sites and may be derived from point industrial sources.
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Affiliation(s)
- M T Jackson
- School of Earth and Ocean Sciences, Cardiff University, Main Building, Cardiff, United Kingdom.
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Prichard HM, Jackson MT, Sampson J. Dispersal and accumulation of Pt, Pd and Rh derived from a roundabout in Sheffield (UK): From stream to tidal estuary. Sci Total Environ 2008; 401:90-99. [PMID: 18486195 DOI: 10.1016/j.scitotenv.2008.03.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2007] [Revised: 03/22/2008] [Accepted: 03/26/2008] [Indexed: 05/26/2023]
Abstract
The Coisley Hill roundabout, a typical urban source for PGE in stream sediments, has anomalously high values of up to 408 ppb Pt, 444 ppb Pd and 113 ppb Rh in road dust, up to 416 ppb Pt and 278 ppb Pd in gulley sediment and up to 606 ppb Pt and 1050 ppb Pd in verge soil. For samples collected at the same time, the road dust values are much higher than in sediments in the Shire Brook stream, that drains the roundabout, with values of 3-64 ppb Pt, 4-57 ppb Pd and up to 7 ppb Rh. Downstream sediments from rivers Rother and Don have lower values of 2-35 ppb Pt, 2-14 ppb Pd and up to 3 ppb Rh. The Humber estuary values are low with 6-8 ppb Pt, 5-8 ppb Pd and 1-2 ppb Rh. Pt/Pd increases down catchment with Coisley Hill 0.8, Shire Brook 1.0, Trent and Don 1.5 and the Humber estuary 2.0. Pt/Rh and Pd/Rh also increase downstream. Precious metals are generally dispersed away from their vehicle catalytic source and Pd is dispersed more than Pt and Rh but Pt and Pd are re-concentrated in acid mine drainage in the Shire Brook, with concentrations varying with stream flow. Pt and Pd values are slightly elevated at the tidal limit and in mud deposited when the river is in spate. On Coisley Hill, values of 133 ppb Pt and 230 ppb Pd occur in dust from a new road surface (two weeks old when sampled). These are similar to those on much older road surfaces suggesting that Pt and Pd collect and disperse rapidly from roads. Au is low in road dust and higher values in conurbations suggest the presence of more Au sources in urban rather than in rural areas. Au values are not diluted downstream as much as PGE suggesting different processes of dispersion and sedimentation.
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Affiliation(s)
- H M Prichard
- School of Earth and Ocean Sciences, Cardiff University, Main Building, Park Place, Cardiff, CF10 3YE, United Kingdom.
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Jackson MT, Sampson J, Prichard HM. Platinum and palladium variations through the urban environment: evidence from 11 sample types from Sheffield, UK. Sci Total Environ 2007; 385:117-31. [PMID: 17673280 DOI: 10.1016/j.scitotenv.2007.06.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2007] [Revised: 05/31/2007] [Accepted: 06/01/2007] [Indexed: 05/16/2023]
Abstract
Platinum (Pt) and Palladium (Pd) concentrations have been analysed in 194 samples from within the city of Sheffield in the UK. The samples were taken from road dust, gully pots (also known as drains), soils, a motorway drainage pipe, rivers, lakes, sewage sludge, incinerator ash, incinerator ash in landfill, street cleansers and gully cleansers. The introduction of Pt- and Pd-bearing automobile catalysts, has been cited as the cause of a rise in the concentration of urban Pt and Pd accumulations. Geochemical analyses for the different sample types are used here to show how the Pt and Pd accumulate in different urban environments as they are transported from their catalytic source. Initially Pt and Pd collect in road dust and gully pots at values of up to 450 ppb although most analyses for both elements are around 100 ppb. The four roadside soils analysed, have a great range in values, the highest with a value of over 600 ppb Pt and 1000 ppb Pd. Then the fate of the Pt and Pd is either to be removed by gully flushers and road sweepers (which contain around half the concentration of that in road dust) or to be washed from the roads, through the gully pots, into either the river or urban drainage systems. Due to the addition of terrestrial sediments, river samples contain much reduced values of Pt and Pd, at approximately an order of magnitude lower than in road dust. Similarly, sewage sludge contains Pt and Pd values which are lower than road dust. However, the Pt and Pd analyses are much higher in incinerated sewage (with many samples over 150 ppb for both metals), probably due to the loss of the mass of other material during the incineration process. Weathered incinerator ash in landfill has lower values of Pt and Pd than fresh ash from the incinerator. Although the range in values of Pt and Pd is similar for road dust and gully pot sediments their modal values tell a different story. The mode for Pt is very similar for both road dust and gully pot sediments, at around 100 ppb, whereas there is a drop of 50 ppb in the mode for Pd in the gully pots (from 80 ppb to around 40 ppb). Given that gully pot sediment is derived from road dust, it is suggested that in gully pots, Pd is preferentially mobilized over Pt. Furthermore, a comparison of the modal values of Pt and Pd in river sediments suggests that this process continues into the natural drainage system of the city.
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Affiliation(s)
- M T Jackson
- School of Earth, Ocean and Planetary Sciences, Cardiff University, Main Building, Park Place, Cardiff, CF10 3YE, UK.
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Abstract
One hundred and twenty-two AFLP markers were mapped using an IR64 x Azucena rice doubled-haploid (DH) population. The distribution of these mapped markers was monitored across a set of 48 diverse landraces of rice. Strong statistical associations were observed between 960 of the 7381 possible pairs of markers across the diverse material. These 960 strongly associated pairs of markers mapped to the same chromosomes in only 111 cases. The remaining 849 pairs were the result of association between markers found on different chromosomes. More than 21% of these genetically unlinked but strongly associated markers are not randomly distributed across the genome but instead occupy blocks of DNA on different rice chromosomes. Amongst associated blocks, there has clearly been maintenance of combinations of marker alleles across very diverse germplasm. Analyses have also revealed that markers are found in association with performance for each of four quantitative traits in both the diverse landrace material and a DH mapping population. It is proposed that the present data provide strong evidence for the co-adaptation of geographically distinct landraces and that this has resulted over time in the maintenance of 'adaptive gene complexes' involving agronomically important quantitative traits.
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Affiliation(s)
- B V Ford-Lloyd
- School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
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Abstract
In this article an implementation of a vocal tract model and its validation are described. The model uses a transmission line model to calculate pole and zero frequencies for a vocal tract with a closed side-branch such as a sublingual cavity. In the validation study calculated pole and zero frequencies from the model are compared with frequencies estimated using elementary acoustic formulas for a variety of vocal tract configurations.
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Affiliation(s)
- M T Jackson
- Department of Electrical and Computer Engineering, Boston University, Massachusetts 02215, USA.
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Jackson MT. Comment on the review of Speech Production and Perception I. Phonetica 1999; 56:103-104. [PMID: 10450078 DOI: 10.1159/000028443] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Affiliation(s)
- M T Jackson
- Sensimetrics Corporation, Somerville, Mass. 02144-2500, USA.
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Abstract
Rice genetic resources, comprising landrace varieties, modern and obsolete varieties, genetic stocks, breeding lines, and the wild rices, are the basis of world food security. The International Rice Genebank at the International Rice Research Institute in the Philippines conserves the largest and most diverse collection of rice germplasm. The facilities of the genebank ensure the long-term preservation of this important diversity. In field research, factors that affect long-term viability of rice seeds have been identified, leading to the introduction of modified practices for germplasm multiplication and regeneration. The value of conserved germplasm can be assessed in terms of useful traits for rice breeding and the economic impact that germplasm utilization has on rice production and productivity. The application of molecular markers is changing perspectives on germplasm management. International policies affecting access to and use of rice germplasm are discussed.
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Affiliation(s)
- M T Jackson
- Genetic Resources Center, International Rice Research Institute, Manila, Philippines
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Pecaric M, Jackson MT, Frampton RR, Maloan J, Buick F. Implementation of a computer-controlled life support system in the acceleration research environment. SAFE J 1996; 26:54-61. [PMID: 11543405] [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] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Electronic control of the G-valve and pressure breathing regulator is being implemented in some advanced life support systems used in aircrew protection. This technological improvement, however, has not reached its full potential in the research environment. A computer-controlled life support system interface providing programmable schedules for G-suit inflation and positive pressure breathing during +Gz (PBG) was developed. Output pressures from a G-valve and pressure breathing regulator (Carleton Technologies) were controlled by a Macintosh computer running LabVIEW software. Required pressures were determined as functions of single or multiple control inputs (i.e. +Gz level, a pressure signal, time, etc.). Subject safety was ensured via hardware limitations and status checks incorporated into the software. Experiments conducted at +1 Gz and at various +Gz levels evaluated the computer software-life support hardware interface. Open-loop algorithms allowed independent control of multiple regulators using simple (single input) and complex (multiple input with adaptive loop) control structures. The system provided accurate and reproducible G-suit and mask pressures. Time of inflation, peak pressure attained, and deflation rate were effectively controlled at all +Gz levels. The ability to alter the pressure schedules independent of +Gz or time allowed comprehensive control over all parameters necessary to conduct acceleration research involving advanced life support systems.
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Affiliation(s)
- M Pecaric
- Defence and Civil Institute of Environmental Medicine, Ontario
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Abstract
Edwardsiella tarda infections are uncommon and have often been reported in association with pet reptiles. The majority of these infections occur as gastrointestinal disorders in immunocompromised hosts. We believe this to be the first reported American case of tuboovarian abscess caused by this organism in an otherwise healthy woman whose only known exposure was to raw seafood. This patient had fever and lower abdominal pain caused by a severe Edwardsiella tarda pelvic abscess that required surgical drainage and intravenous antibiotics for complete recovery.
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Affiliation(s)
- F D Pien
- Department of Infectious Diseases, Straub Clinic & Hospital, Inc., Honolulu, Hawaii, USA
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Virk PS, Newbury HJ, Jackson MT, Ford-Lloyd BV. The identification of duplicate accessions within a rice germplasm collection using RAPD analysis. Theor Appl Genet 1995; 90:1049-55. [PMID: 24173061 DOI: 10.1007/bf00222920] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/1994] [Accepted: 12/08/1994] [Indexed: 05/08/2023]
Abstract
A set of accessions of Oryza sativa from the International Rice Research Institute (Philippines) that included known and suspected duplicates as well as closely related germplasm has been subjected to RAPD analysis. The number of primers, the number of polymorphic bands and the total number of bands were determined that will allow the accurate discrimination of these categories of accessions, including the identification of true and suspected duplicates. Two procedures have been described that could be employed on a more general basis for identifying duplicates in genetic resources collections, and further discussion on the values of such activities is presented.
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Affiliation(s)
- P S Virk
- School of Biological Sciences, University of Birmingham, B15 2TT, Edgbaston, Birmingham, UK
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Abstract
As part of the development of a molecular toolkit for the study of diversity within large plant germplasm collections, RAPD technology has been applied to accessions of rice (Oryza sativa) obtained from the major world collection held at IRRI (the International Rice Research Institute) which supplies germplasm to breeders. Methods for the speedy extraction of DNA representative of a rice accession, its amplification by PCR to reveal reproducible products, and the analysis of the banding data using numerical techniques have been established. The biological meaningfulness of RAPD data has also been demonstrated by reference to previous work on classification and crossability.
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Affiliation(s)
- P S Virk
- School of Biological Sciences, University of Birmingham, U.K
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Perkell JS, Cohen MH, Svirsky MA, Matthies ML, Garabieta I, Jackson MT. Electromagnetic midsagittal articulometer systems for transducing speech articulatory movements. J Acoust Soc Am 1992; 92:3078-96. [PMID: 1474223 DOI: 10.1121/1.404204] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
This paper describes two electromagnetic midsagittal articulometer (EMMA) systems that were developed for transducing articulatory movements during speech production. Alternating magnetic fields are generated by transmitter coils that are mounted in an assembly that fits on the head of a speaker. The fields induce alternating voltages in a number of small transducer coils that are attached to articulators in the midline plane, inside and outside the vocal tract. The transducers are connected by fine lead wires to receiver electronics whose output voltages are processed to yield measures of transducer locations as a function of time. Measurement error can arise with this method, because as the articulators move and change shape, the transducers can undergo a varying amount of rotational misalignment with respect to the transmitter axes; both systems are designed to correct for transducer misalignment. For this purpose, one system uses two transmitters and biaxial transducers; the other uses three transmitters and single-axis transducers. The systems have been compared with one another in terms of their performance, human subjects compatibility, and ease of use. Both systems can produce useful midsagittal-plane data on articular movement, and each one has a specific set of advantages and limitations. (Two commercially available systems are also described briefly for comparison purposes). If appropriate experimental controls are used, the three-transmitter system is preferable for practical reasons.
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Affiliation(s)
- J S Perkell
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge 02139
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Hawkes JG, Jackson MT. Taxonomic and evolutionary implications of the Endosperm Balance Number hypothesis in potatoes. Theor Appl Genet 1992; 84:180-185. [PMID: 24203045 DOI: 10.1007/bf00223998] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/1991] [Accepted: 10/17/1991] [Indexed: 06/02/2023]
Abstract
The Endosperm Balance Number (EBN) hypothesis can explain to a considerable degree the crossability between tuber-bearing Solanum species. It has been shown to be genetically controlled and is dosage dependent. There is a good correlation between EBN and the postulated evolution and present taxonomy of potatoes. The primitive white stellate-flowered species from Mexico are 1EBN, and this condition is also found in species from South America with flowers of the same colour and shape. The evolution of a rotate corolla seems to be correlated with 2EBN. It is postulated that the 2EBN state arose as a reproductive isolating mechanism in South America. The taxonomic and evolutionary implications of the EBN hypothesis are discussed.
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Affiliation(s)
- J G Hawkes
- School of Continuing Studies, The University of Birmingham, B15 2TT, Edgbaston, Birmingham, UK
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Jackson MT. Biotechnology and the environment: a Birmingham perspective. J Biotechnol 1991; 17:195-7. [PMID: 1367096 DOI: 10.1016/0168-1656(91)90010-s] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- M T Jackson
- Plant Genetics Group, School of Biological Sciences, University of Birmingham, Edgbaston, U.K
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Jackson MT, Oldfield ML. The Value of Conserving Genetic Resources. J Appl Ecol 1986. [DOI: 10.2307/2404053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Duff P, Jackson MT. Pregnancy complicated by rhesus sensitization and the May-Hegglin anomaly. Obstet Gynecol 1985; 65:7S-10S. [PMID: 3919350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The authors describe a pregnancy complicated by rhesus sensitization and the May-Hegglin anomaly. The principal objective in caring for the patient was prevention of maternal and fetal hemorrhage. Transfusion of type-specific platelets corrected the patient's abnormal bleeding time. Cesarean section resulted in delivery of a healthy, but thrombocytopenic, infant who subsequently was shown to have the May-Hegglin defect.
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Kaminski DA, Jackson MT. A Light and Moisture Continuum Analysis of the Presettlement Prairie-Forest Border Region of Eastern Illinois. American Midland Naturalist 1978. [DOI: 10.2307/2424806] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Jackson MT, Faller A. Structural Analysis and Dynamics of the Plant Communities of Wizard Island, Crater Lake National Park. ECOL MONOGR 1973. [DOI: 10.2307/1942302] [Citation(s) in RCA: 8] [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: 11/10/2022]
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Jackson MT, Petty RO. An Assessment of Various Synthetic Indices in a Transitional Old-Growth Forest. American Midland Naturalist 1971. [DOI: 10.2307/2423682] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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