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McCabe MC, Okamura DM, Erickson CB, Perry BW, Brewer CM, Nguyen ED, Saviola AJ, Majesky MW, Hansen KC. ECM-Focused Proteomic Analysis of Ear Punch Regeneration in Acomys Cahirinus. bioRxiv 2023:2023.10.11.561940. [PMID: 37873317 PMCID: PMC10592745 DOI: 10.1101/2023.10.11.561940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
In mammals, significant injury is generally followed by the formation of a fibrotic scar which provides structural integrity but fails to functionally restore damaged tissue. Spiny mice of the genus Acomys represent the first example of full skin autotomy in mammals. Acomys cahirinus has evolved extremely weak skin as a strategy to avoid predation and is able to repeatedly regenerate healthy tissue without scar after severe skin injury or full-thickness ear punches. Extracellular matrix (ECM) composition is a critical regulator of wound repair and scar formation and previous studies have suggested that alterations in its expression may be responsible for the differences in regenerative capacity observed between Mus musculus and A. cahirinus , yet analysis of this critical tissue component has been limited in previous studies by its insolubility and resistance to extraction. Here, we utilize a 2-step ECM-optimized extraction to perform proteomic analysis of tissue composition during wound repair after full-thickness ear punches in A. cahirinus and M. musculus from weeks 1 to 4 post-injury. We observe changes in a wide range of ECM proteins which have been previously implicated in wound regeneration and scar formation, including collagens, coagulation and provisional matrix proteins, and matricryptic signaling peptides. We additionally report differences in crosslinking enzyme activity and ECM protein solubility between Mus and Acomys. Furthermore, we observed rapid and sustained increases in CD206, a marker of pro-regenerative M2 macrophages, in Acomys, whereas little or no increase in CD206 was detected in Mus. Together, these findings contribute to a comprehensive understanding of tissue cues which drive the regenerative capacity of Acomys and identify a number of potential targets for future pro-regenerative therapies.
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Okamura DM, Brewer CM, Wakenight P, Bahrami N, Bernardi K, Tran A, Olson J, Shi X, Yeh SY, Piliponsky A, Collins SJ, Nguyen ED, Timms AE, MacDonald JW, Bammler TK, Nelson BR, Millen KJ, Beier DR, Majesky MW. Spiny mice activate unique transcriptional programs after severe kidney injury regenerating organ function without fibrosis. iScience 2021; 24:103269. [PMID: 34849462 PMCID: PMC8609232 DOI: 10.1016/j.isci.2021.103269] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [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: 03/25/2021] [Revised: 09/02/2021] [Accepted: 10/12/2021] [Indexed: 12/13/2022] Open
Abstract
Fibrosis-driven solid organ failure is an enormous burden on global health. Spiny mice (Acomys) are terrestrial mammals that can regenerate severe skin wounds without scars to avoid predation. Whether spiny mice also regenerate internal organ injuries is unknown. Here, we show that despite equivalent acute obstructive or ischemic kidney injury, spiny mice fully regenerate nephron structure and organ function without fibrosis, whereas C57Bl/6 or CD1 mice progress to complete organ failure with extensive renal fibrosis. Two mechanisms for vertebrate regeneration have been proposed that emphasize either extrinsic (pro-regenerative macrophages) or intrinsic (surviving cells of the organ itself) controls. Comparative transcriptome analysis revealed that the Acomys genome appears poised at the time of injury to initiate regeneration by surviving kidney cells, whereas macrophage accumulation was not detected until about day 7. Thus, we provide evidence for rapid activation of a gene expression signature for regenerative wound healing in the spiny mouse kidney.
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Affiliation(s)
- Daryl M. Okamura
- Department of Pediatrics, University of Washington, Seattle, WA 98195, USA
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Chris M. Brewer
- Department of Laboratory Medicine & Pathology, University of Washington, Seattle, WA 98195, USA
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Paul Wakenight
- Center for Integrated Brain Research, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Nadia Bahrami
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Kristina Bernardi
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Amy Tran
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Jill Olson
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Xiaogang Shi
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Szu-Ying Yeh
- Center for Integrated Brain Research, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Adrian Piliponsky
- Center for Immunity & Immunotherapies, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Sarah J. Collins
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Elizabeth D. Nguyen
- Department of Pediatrics, University of Washington, Seattle, WA 98195, USA
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Andrew E. Timms
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - James W. MacDonald
- Department of Environmental & Occupational Health, University of Washington, Seattle, WA 98195, USA
| | - Theo K. Bammler
- Department of Environmental & Occupational Health, University of Washington, Seattle, WA 98195, USA
| | - Branden R. Nelson
- Center for Integrated Brain Research, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Kathleen J. Millen
- Department of Pediatrics, University of Washington, Seattle, WA 98195, USA
- Center for Integrated Brain Research, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - David R. Beier
- Department of Pediatrics, University of Washington, Seattle, WA 98195, USA
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - Mark W. Majesky
- Department of Pediatrics, University of Washington, Seattle, WA 98195, USA
- Department of Laboratory Medicine & Pathology, University of Washington, Seattle, WA 98195, USA
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98105, USA
- Institute of Stem Cell & Regenerative Medicine, University of Washington, Seattle, WA 98195, USA
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Brewer CM, Nelson BR, Wakenight P, Collins SJ, Okamura DM, Dong XR, Mahoney WM, McKenna A, Shendure J, Timms A, Millen KJ, Majesky MW. Adaptations in Hippo-Yap signaling and myofibroblast fate underlie scar-free ear appendage wound healing in spiny mice. Dev Cell 2021; 56:2722-2740.e6. [PMID: 34610329 DOI: 10.1016/j.devcel.2021.09.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 06/10/2021] [Accepted: 09/13/2021] [Indexed: 12/21/2022]
Abstract
Spiny mice (Acomys cahirinus) are terrestrial mammals that evolved unique scar-free regenerative wound-healing properties. Myofibroblasts (MFs) are the major scar-forming cell type in skin. We found that following traumatic injury to ear pinnae, MFs appeared rapidly in both Acomys and mouse yet persisted only in mouse. The timing of MF loss in Acomys correlated with wound closure, blastema differentiation, and nuclear localization of the Hippo pathway target protein Yap. Experiments in vitro revealed an accelerated PP2A-dependent dephosphorylation activity that maintained nuclear Yap in Acomys dermal fibroblasts (DFs) and was not detected in mouse or human DFs. Treatment of Acomys in vivo with the nuclear Yap-TEAD inhibitor verteporfin prolonged MF persistence and converted tissue regeneration to fibrosis. Forced Yap activity prevented and rescued TGF-β1-induced human MF formation in vitro. These results suggest that Acomys evolved modifications of Yap activity and MF fate important for scar-free regenerative wound healing in vivo.
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Affiliation(s)
- Chris M Brewer
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA 98195, USA; Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Branden R Nelson
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA.
| | - Paul Wakenight
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Sarah J Collins
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Daryl M Okamura
- Department of Pediatrics, University of Washington, Seattle, WA 98195, USA; Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Xiu Rong Dong
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - William M Mahoney
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA 98195, USA
| | - Aaron McKenna
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| | - Jay Shendure
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA; Howard Hughes Medical Institute, Seattle, WA 98195, USA
| | - Andrew Timms
- Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Kathleen J Millen
- Department of Pediatrics, University of Washington, Seattle, WA 98195, USA; Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA.
| | - Mark W Majesky
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA 98195, USA; Department of Pediatrics, University of Washington, Seattle, WA 98195, USA; Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, WA 98101, USA.
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Affiliation(s)
- Xiu Rong Dong
- From the Center for Developmental Biology and Regenerative Medicine (X.R.D., C.M.B., M.W.M.), University of Washington, Seattle
| | - Chris M Brewer
- From the Center for Developmental Biology and Regenerative Medicine (X.R.D., C.M.B., M.W.M.), University of Washington, Seattle
| | - Mark W Majesky
- From the Center for Developmental Biology and Regenerative Medicine (X.R.D., C.M.B., M.W.M.), University of Washington, Seattle.,Department of Pediatrics, Seattle Children's Research Institute (M.W.M.), University of Washington, Seattle.,Department of Pathology (M.W.M.), University of Washington, Seattle
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Affiliation(s)
- Chris M Brewer
- From the Center for Developmental Biology and Regenerative Medicine, Seattle Children's Research Institute (C.M.B., M.W.M.), Department of Pediatrics (M.W.M.), Department of Pathology (C.M.B., M.W.M.), and Molecular Basis of Disease Graduate Program (C.M.B., M.W.M.), University of Washington, Seattle
| | - Mark W Majesky
- From the Center for Developmental Biology and Regenerative Medicine, Seattle Children's Research Institute (C.M.B., M.W.M.), Department of Pediatrics (M.W.M.), Department of Pathology (C.M.B., M.W.M.), and Molecular Basis of Disease Graduate Program (C.M.B., M.W.M.), University of Washington, Seattle.
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Welch H, Brewer CM. Relative Toxicity of Certain Antiseptics Containing Soap and Alcohol-With Special Reference to Mouth Washes. Am J Public Health Nations Health 2008; 32:261-7. [PMID: 18015580 DOI: 10.2105/ajph.32.3.261] [Citation(s) in RCA: 3] [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: 11/04/2022]
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Affiliation(s)
- C M Brewer
- Department of Bacteriology, University of Maryland, College Park, Maryland
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Ellard S, Hattersley AT, Brewer CM, Vaidya B. Detection of an MEN1 gene mutation depends on clinical features and supports current referral criteria for diagnostic molecular genetic testing. Clin Endocrinol (Oxf) 2005; 62:169-75. [PMID: 15670192 DOI: 10.1111/j.1365-2265.2005.02190.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Diagnostic molecular genetic testing for multiple endocrine neoplasia type 1 (MEN1) has been available since the identification of the MEN1 gene in 1997. Mutation screening of the MEN1 gene has been recommended for patients who meet clinical criteria for MEN1 (at least two of the following: parathyroid hyperplasia, pancreatic endocrine tumour or pituitary adenoma) and those in whom a diagnosis of MEN1 is suspected. We examined the appropriateness of these clinical criteria. PATIENTS AND METHODS A total of 292 patients were referred for diagnostic testing. The coding region of the MEN1 gene was sequenced in 186 index cases and mutation testing was requested for 106 subjects, including 83 asymptomatic relatives. RESULTS MEN1 gene mutations were identified in 68/186 index cases (37%). Twenty-nine of the 60 MEN1 mutations reported are novel. The likelihood of finding a mutation was correlated with the number of MEN1-related tumours (mutation detection rate of 79%, 37% and 15% in patients with three, two and one main MEN1-related tumours; P < or = 0.00001) and increased in the presence of a family history (mutation detection rate of 91%, 69% and 29%vs. 69%, 23% and 0% in sporadic cases with three, two or one main MEN1-related tumours, respectively; P < or = 0.00001). The pick-up rate in the 83% of subjects who met proposed criteria for diagnostic testing was 42%, but in those who did not meet these criteria this fell to 0%. CONCLUSIONS The likelihood of finding an MEN1 mutation depends on the clinical features of the patient and their family. This large series supports present referral criteria for diagnostic mutation screening, but suggests that patients with sporadic isolated tumours rarely have MEN1 mutations.
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Affiliation(s)
- S Ellard
- Department of Molecular Genetics, Royal Devon & Exeter NHS Foundation Trust, Exeter, UK.
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Brewer CM, Holloway SH, Stone DH, Carothers AD, FitzPatrick DR. Survival in trisomy 13 and trisomy 18 cases ascertained from population based registers. J Med Genet 2002; 39:e54. [PMID: 12205124 PMCID: PMC1735241 DOI: 10.1136/jmg.39.9.e54] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Brewer CM, Leek JP, Green AJ, Holloway S, Bonthron DT, Markham AF, FitzPatrick DR. A locus for isolated cleft palate, located on human chromosome 2q32. Am J Hum Genet 1999; 65:387-96. [PMID: 10417281 PMCID: PMC1377937 DOI: 10.1086/302498] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
We present evidence for the existence of a novel chromosome 2q32 locus involved in the pathogenesis of isolated cleft palate. We have studied two unrelated patients with strikingly similar clinical features, in whom there are apparently balanced, de novo cytogenetic rearrangements involving the same region of chromosome 2q. Both children have cleft palate, facial dysmorphism, and mild learning disability. Their karyotypes were originally reported as 46, XX, t(2;7)(q33;p21) and 46, XX, t(2;11)(q33;p14). However, our molecular cytogenetic analyses localize both translocation breakpoints to a small region between markers D2S311 and D2S116. This suggests that the true location of these breakpoints is 2q32 rather than 2q33. To obtain independent support for the existence of a cleft-palate locus in 2q32, we performed a detailed statistical analysis for all cases in the human cytogenetics database of nonmosaic, single, contiguous autosomal deletions associated with orofacial clefting. This revealed 2q32 to be one of only three chromosomal regions in which haploinsufficiency is significantly associated with isolated cleft palate. In combination, our data provide strong evidence for the location at 2q32 of a gene that is critical to the development of the secondary palate. The close proximity of these two translocation breakpoints should also allow rapid progress toward the positional cloning of this cleft-palate gene.
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Affiliation(s)
- C M Brewer
- Human Genetics Unit, University of Edinburgh, and Department of Clinical Genetics, Western General Hospital, Edinburgh, UK
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Abstract
Molecular genetic investigation of a female infant with Beckwith-Wiedemann syndrome (BWS) showed loss of IGF2 imprinting but no evidence of uniparental disomy. In addition, a deletion of chromosome 18q22.1 was identified in this infant without clinical features of 18q-syndrome (microcephaly, short stature, hypotonia). The association of a chromosome 18 deletion and BWS may be coincidental or may indicate the location of a trans activating regulator element for maintenance of IGF2 imprinting.
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Affiliation(s)
- C M Brewer
- Human Genetics Unit, Western General Hospital, Edinburgh, UK
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Brewer CM, Grace E, Stark GD, Gregory DW, Howell RT, Fitzpatrick DR. Genomic instability associated with limb defects: case report and review of the literature. Clin Dysmorphol 1997; 6:99-109. [PMID: 9134289] [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: 02/04/2023]
Abstract
We report a child in whom we observed markedly increased genome-wide spontaneous chromosomal breakage in both leucocytes and fibroblasts associated with severe growth retardation, radial aplasia, leucopenia, mild hydrocephalus and an unusual trichodystrophy. Exposure to DNA cross-linking agents diepoxybutane, mitomycin-C and mustine hydrochloride in this case did not result in the increased chromosome breakage seen in Fanconi anaemia. It may be that this child has a defect in postreplicative DNA repair interacting with the protein components deficient in FA.
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Brewer CM, Fredericks BJ, Pont JM, Stephenson JB, Tolmie JL. X-linked hydrocephalus masquerading as spina bifida and destructive porencephaly in successive generations in one family. Dev Med Child Neurol 1996; 38:632-6. [PMID: 8674913 DOI: 10.1111/j.1469-8749.1996.tb12127.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The authors report a case of X-linked hydrocephalus which presented as a destructive porencephaly. There was asymmetric dilatation of the ventricles of prenatal onset, and neuro-imagining studies were suggestive of infection or haemorrhage. The child was profoundly handicapped but did not have adducted thumbs. Two of his mother's brothers had been stillborn, and postmortem reports revealed that the diagnosis had been isolated hydrocephalus and not spina bifida as reported by the family. Despite serial ultrasound scans, recurrence of X-linked hydrocephalus in the mother's subsequent pregnancy was not detected until 26 weeks gestation, when the ventricles became grossly dilated. The diagnosis was confirmed in this family by identification of a mutation within the LICAM gene.
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Affiliation(s)
- C M Brewer
- Department of Clinical Genetics, Western General Hospital, Edinburgh, UK
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Brewer CM, Fredericks BJ, Pont JM, Stephenson JB, Tolmie JL. X-linked hydrocephalus masquerading as spina bifida and destructive porencephaly in successive generations in one family. Dev Med Child Neurol 1996; 38:359-63. [PMID: 8641541 DOI: 10.1111/j.1469-8749.1996.tb12102.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The authors report a case of X-linked hydrocephalus which presented as a destructive porencephaly. There was asymmetric dilatation of the ventricles of prenatal onset, and neuro-imagining studies were suggestive of infection or haemorrhage. The child was profoundly handicapped but did not have adducted thumbs. Two of his mother's brothers had been stillborn, and postmortem reports revealed that the diagnosis had been isolated hydrocephalus and not spina bifida as reported by the family. Despite serial ultrasound scans, recurrence of X-linked hydrocephalus in the mother's subsequent pregnancy was not detected until 26 weeks gestation, when the ventricles became grossly dilated. The diagnosis was confirmed in this family by identification of mutation within the L1CAM gene.
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Affiliation(s)
- C M Brewer
- Department of Clinical Genetics, Western General Hospital, Edinburgh, UK
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Abstract
Sixteen children and adolescents with a firm clinical diagnosis of Williams syndrome were investigated with the chromosome fluorescence in situ hybridisation (FISH) technique employing the elastin gene probe. In each case there was a fluorescent signal on one chromosome 7 homologue only, indicating elastin gene deletion. No deletion was demonstrated in another child in whom an earlier diagnosis of Williams syndrome was judged doubtful at review. Firm clinical diagnosis correlates with elastin gene deletion in 16/16 cases of Williams syndrome and detection of such hemizygosity by FISH constitutes a useful confirmatory diagnostic test.
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Affiliation(s)
- C M Brewer
- Duncan Guthrie Institute of Medical Genetics, Royal Hospital for Sick Children, Glasgow
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Abstract
Baclofen appears to be an agonist for the bicuculline-insensitive gamma-aminobutyrateB receptors associated with C fibre terminals in the dorsal horn of the spinal cord. We have tested the effect of baclofen (applied intrathecally onto the spinal cord) on the A and C fibre-evoked responses of convergent/multireceptive neurones in the halothane-anaesthetized rat. L-Baclofen produced a dose-dependent inhibition of the C fibre- and pinch-evoked activity of these neurones which persisted for 2 h whilst the A fibre and tactile activities were little changed. The C fibre-evoked (X 3 threshold) responses were markedly or completely inhibited 10 min after doses of between 0.25 and 30 micrograms of L-baclofen (n = 21) with 0.05 micrograms causing a 48% (n = 3) and 0.01 micrograms a 28% inhibition (n = 3). D-Baclofen (30 micrograms), the inactive isomer, produced no significant changes in activity (n = 10). Bicuculline (60 micrograms) applied intrathecally before (n = 7) or after (n = 8) L-baclofen did not reverse the inhibitions. Intravenous baclofen (1-3 mg/kg) also produced neuronal inhibitions similar to the effects of intrathecal injection. The results suggest that gamma-aminobutyrateB receptors may exert a presynaptic control of C fibre afferents in the dorsal horn following intrathecal administration in the rat.
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Affiliation(s)
- C M Brewer
- War Food Administration, Office of Distribution, Livestock and Meats Branch, Insecticide Division, Beltsville, Md
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Affiliation(s)
- C M Brewer
- Insecticide Division, Livestock and Meats Branch, Food Distribution Administration, Beltsville, Md
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Affiliation(s)
- C M Brewer
- U. S. Food and Drug Administration, Washington, D. C
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Affiliation(s)
- C M Brewer
- U. S. Food and Drug Administration, Washington, D. C
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