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Desroches S, Lapointe A, Deschênes SM, Bissonnette-Maheux V, Gravel K, Thirsk J, Légaré F. Dietitians' Perspectives on Interventions to Enhance Adherence to Dietary Advice for Chronic Diseases in Adults. CAN J DIET PRACT RES 2015; 76:103-8. [PMID: 26280789 DOI: 10.3148/cjdpr-2015-009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
PURPOSE To assess dietitians' perspectives on the importance and applicability of interventions to enhance adherence to dietary advice for preventing and managing chronic diseases in adults in the Canadian context. METHODS Based on a Cochrane systematic review, we identified 8 promising interventions for enhancing adherence to dietary advice: behavioural contracts, exchange lists, feedback based on self-monitoring, individualized menu suggestions, multiple interventions, portion size awareness, telephone follow-up, and videos. Thirty-two dietitians then completed a 3-round Delphi study by responding to an electronic questionnaire asking them to rate the importance and applicability in their practice of the 8 interventions on a 7-point Likert scale. RESULTS Using a ≥75% level of agreement, 4 interventions showed strong consensus: multiple interventions, feedback based on self-monitoring, portion size awareness, and videos. Among these, the most significant were (means ± SD for importance and applicability, respectively) feedback based on self-monitoring (6.97 ± 0.18 and 6.72 ± 0.46), portion size awareness (6.69 ± 0.54 and 6.75 ± 0.51), and multiple interventions (6.94 ± 0.25 and 6.81 ± 0.40). CONCLUSIONS These findings can guide the development of educational training sessions for dietitians to help them provide practice-relevant interventions that will increase the likelihood that patients adhere to their advice regarding prevention and management of chronic diseases.
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Affiliation(s)
- Sophie Desroches
- a CHUQ Research Center, Centre Hospitalier Universitaire de Québec, Hôpital St-François d'Assise, Laval University, Quebec, QC.,b Institute of Nutrition and Functional Foods, Laval University, Quebec, QC
| | - Annie Lapointe
- b Institute of Nutrition and Functional Foods, Laval University, Quebec, QC
| | | | | | - Karine Gravel
- b Institute of Nutrition and Functional Foods, Laval University, Quebec, QC
| | - Jayne Thirsk
- c Practice-based Evidence in Nutrition, Dietitians of Canada, Calgary, AB
| | - France Légaré
- a CHUQ Research Center, Centre Hospitalier Universitaire de Québec, Hôpital St-François d'Assise, Laval University, Quebec, QC.,d Department of Family Medicine and Emergency Medicine, Laval University, Quebec, QC
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Vaillancourt H, Légaré F, Gagnon MP, Lapointe A, Deschênes SM, Desroches S. Exploration of shared decision-making processes among dieticians and patients during a consultation for the nutritional treatment of dyslipidaemia. Health Expect 2014; 18:2764-75. [PMID: 25135143 DOI: 10.1111/hex.12250] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/21/2014] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Shared decision making (SDM) holds great potential for improving the therapeutic efficiency and quality of nutritional treatment of dyslipidaemia by promoting patient involvement in decision making. Adoption of specific behaviours fostering SDM during consultations has yet to be studied in routine dietetic practice. OBJECTIVE Using a cross-sectional study design, we aimed to explore both dieticians' and patients' adoption of SDM behaviours in dietetic consultations regarding the nutritional treatment of dyslipidaemia. METHODS Twenty-six dieticians working in local health clinics in the Quebec City metropolitan area were each asked to identify one dyslipidaemic patient they would see in an upcoming consultation. Based on the Theory of Planned Behaviour (TPB), questionnaires were designed to study two targeted SDM behaviours: 'to discuss nutritional treatment options for dyslipidaemia' and 'to discuss patients' values and preferences about nutritional treatment options for dyslipidaemia'. These questionnaires were administered to the dietician-patient dyad individually before the consultation. Associations between TPB constructs (attitude, subjective norm and perceived behavioural control) towards behavioural intentions were analysed using Spearman's partial correlations. RESULTS Thirteen unique patient-dietician dyads completed the study. Perceived behavioural control was the only TPB construct significantly associated with both dieticians' and patients' intentions to adopt the targeted SDM behaviours (P < 0.05). CONCLUSIONS As perceived behavioural control seems to determine dieticians' and patients' adoption of SDM behaviours, interventions addressing barriers and reinforcing enablers of these behaviours are indicated. This exploratory study highlights issues that could be addressed in future research endeavours to expand the knowledge base relating to SDM adoption in dietetic practice.
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Affiliation(s)
- Hugues Vaillancourt
- Institute on Nutrition and Functional Foods (INAF), Laval University, Quebec City, QC, Canada.,Department of Food and Nutrition Sciences, Faculty of Agriculture and Food Sciences, Laval University, Quebec City, QC, Canada
| | - France Légaré
- CHUQ Research Center (Centre Hospitalier Universitaire de Québec - Hôpital St-François-d'Assise), Quebec City, QC, Canada.,Department of Family and Emergency Medicine, Faculty of Medicine, Laval University, Quebec City, QC, Canada
| | - Marie-Pierre Gagnon
- CHUQ Research Center (Centre Hospitalier Universitaire de Québec - Hôpital St-François-d'Assise), Quebec City, QC, Canada.,Faculty of Nursing, Laval University, Quebec City, QC, Canada
| | - Annie Lapointe
- Institute on Nutrition and Functional Foods (INAF), Laval University, Quebec City, QC, Canada
| | - Sarah-Maude Deschênes
- Institute on Nutrition and Functional Foods (INAF), Laval University, Quebec City, QC, Canada
| | - Sophie Desroches
- Institute on Nutrition and Functional Foods (INAF), Laval University, Quebec City, QC, Canada.,Department of Food and Nutrition Sciences, Faculty of Agriculture and Food Sciences, Laval University, Quebec City, QC, Canada.,CHUQ Research Center (Centre Hospitalier Universitaire de Québec - Hôpital St-François-d'Assise), Quebec City, QC, Canada
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Desroches S, Lapointe A, Galibois I, Deschênes SM, Gagnon MP. Psychosocial factors and intention to use the nutrition care process among dietitians and dietetic interns. CAN J DIET PRACT RES 2014; 75:e335-41. [PMID: 24606960 DOI: 10.3148/75.1.2014.e335] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
PURPOSE The theory of planned behaviour was used to explore the factors (i.e., attitude, subjective norm, and perceived behavioural control) affecting the intention of dietetic internship educators, new dietetic graduates, and dietetic interns to use the nutrition care process (NCP) in their clinical practice. METHODS Participants (n=55) were recruited from the Bachelor of Science in Nutrition program at Université Laval. They completed an online quantitative questionnaire assessing their intention to use the NCP in their clinical practice, as well as associated psychosocial factors. Open-ended questions were also used to gain a further understanding of the salient beliefs underlying participants' intention to use the NCP. RESULTS Intention to use the NCP in practice and associated psychosocial factors were similar and favourable within the three participant groups. Subjective norm and perceived behavioural control were the psychosocial factors that significantly predicted an intention to use the NCP. The most cited perceived barrier to use of the NCP was a lack of knowledge, while the most cited facilitator was training opportunities. CONCLUSIONS Our results indicate that successful implementation of the NCP will likely require the development of theoretical and practical training activities for both pre-licensure students and experienced dietitians.
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Affiliation(s)
- Sophie Desroches
- Université Laval and Centre Hospitalier Universitaire de Québec-Hôpital St-François d'Assise
| | | | | | | | - Marie-Pierre Gagnon
- Centre Hospitalier Universitaire de Québec-Hôpital St-François d'Assise and Université Laval
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Vaillancourt H, Légaré F, Lapointe A, Deschênes SM, Desroches S. Assessing patients' involvement in decision making during the nutritional consultation with a dietitian. Health Expect 2012; 17:545-54. [PMID: 22512818 DOI: 10.1111/j.1369-7625.2012.00783.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Shared decision making (SDM) represents an interesting approach to optimize the impact of dietary treatment, but there is no evidence that SDM is commonly integrated into diet-related health care. OBJECTIVE To assess the extent to which dietitians involve patients in decisions about dietary treatment. METHODS We audiotaped dietitians conducting nutritional consultations with their patients, and we transcribed the tapes verbatim. Three trained raters independently evaluated the content of the nutritional consultations using a coding frame based on the 12 items of the French-language version of the OPTION scale, a validated and reliable third-observer instrument designed to assess patients' involvement by examining specific health professionals' behaviours. Coding was facilitated by the qualitative research software NVivo 8. We assessed internal consistency with Cronbach's alpha and inter-rater reliability with the intraclass correlation coefficient (ICC). RESULTS Of the 40 dietitians eligible to participate in the study, 19 took part. We recruited one patient per participating dietitian. The overall mean OPTION score was 29 ± 8% [range, 0% (no patient involvement in the decision] to 100% [high patient involvement)]. The mean duration of consultations was 50 ± 26 min. The OPTION score was positively correlated with the duration of the consultation (r = 0.65, P < 0.01). Internal consistency and inter-rater reliability were both good (Cronbach's alpha = 0.72; ICC = 0.65). CONCLUSION This study is the first to use a framework based on the OPTION scale to report on dietitians' involvement of patients in decisions about patients' dietary treatment. The results suggest that involvement is suboptimal. Interventions to increase patients' involvement in diet-related decision making are indicated.
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Affiliation(s)
- Hugues Vaillancourt
- Research Assistant, Institute of Nutraceuticals and Functional Foods (INAF), Laval University, Quebec City, QCAffiliated Researcher, CHUQ Research Center (Centre Hospitalier Universitaire de Québec - Hôpital St-François-d'Assise),Associate Professor, Department of Family and Emergency Medicine, Faculty of Medicine, Laval University, Quebec City, QC,Associate Professor, Department of Food and Nutrition Sciences, Faculty of Agriculture and Food Sciences, Laval University, Quebec City, QC,Affiliated Researcher, Institute of Nutraceuticals and Functional Foods (INAF), Laval University, Quebec City, QC, Canada
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Desroches S, Lapointe A, Deschênes SM, Gagnon MP, Légaré F. Exploring dietitians' salient beliefs about shared decision-making behaviors. Implement Sci 2011; 6:57. [PMID: 21631933 PMCID: PMC3120721 DOI: 10.1186/1748-5908-6-57] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Accepted: 06/01/2011] [Indexed: 11/10/2022] Open
Abstract
Background Shared decision making (SDM), a process by which health professionals and patients go through the decision-making process together to agree on treatment, is a promising strategy for promoting diet-related decisions that are informed and value based and to which patients adhere well. The objective of the present study was to identify dietitians' salient beliefs regarding their exercise of two behaviors during the clinical encounter, both of which have been deemed essential for SDM to take place: (1) presenting patients with all dietary treatment options for a given health condition and (2) helping patients clarify their values and preferences regarding the options. Methods Twenty-one dietitians were allocated to four focus groups. Facilitators conducted the focus groups using a semistructured interview guide based on the Theory of Planned Behavior. Discussions were audiotaped, transcribed verbatim, coded, and analyzed with NVivo8 (QSR International, Cambridge, MA) software. Results Most participants stated that better patient adherence to treatment was an advantage of adopting the two SDM behaviors. Dietitians identified patients, physicians, and the multidisciplinary team as normative referents who would approve or disapprove of their adoption of the SDM behaviors. The most often reported barriers and facilitators for the behaviors concerned patients' characteristics, patients' clinical situation, and time. Conclusions The implementation of SDM in nutrition clinical practice can be guided by addressing dietitians' salient beliefs. Identifying these beliefs also provides the theoretical framework needed for developing a quantitative survey questionnaire to further study the determinants of dietitians' adoption of SDM behaviors.
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Affiliation(s)
- Sophie Desroches
- CHUQ Research Center, Centre Hospitalier Universitaire de Québec-Hôpital St-François-d'Assise, Québec, QC, Canada.
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Abstract
DNA mismatch repair (MMR) is one of multiple replication, repair, and recombination processes that are required to maintain genomic stability in prokaryotes and eukaryotes. In the wake of the discoveries that hereditary nonpolyposis colorectal cancer (HNPCC) and other human cancers are associated with mutations in MMR genes, intensive efforts are under way to elucidate the biochemical functions of mammalian MutS and MutL homologs, and the consequences of defects in these genes. Genetic studies in cultured mammalian cells and mice are proving to be instrumental in defining the relationship between the functions of MMR in mutation and tumor avoidance. Furthermore, these approaches have raised awareness that MMR homologs contribute to DNA damage surveillance, transcription-coupled repair, and recombinogenic and meiotic processes.
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Affiliation(s)
- A B Buermeyer
- Department of Molecular and Medical Genetics, Oregon Health Sciences University, Portland 97201-3098, USA
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Scherer SS, Bone LJ, Deschênes SM, Abel A, Balice-Gordon RJ, Fischbeck KH. The role of the gap junction protein connexin32 in the pathogenesis of X-linked Charcot-Marie-Tooth disease. Novartis Found Symp 1999; 219:175-85; discussion 185-7. [PMID: 10207904 DOI: 10.1002/9780470515587.ch11] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Mutations in the gene encoding the gap junction protein connexin32 (Cx32; beta 1) cause the X-linked form of Charcot-Marie-Tooth disease (CMTX), a common form of inherited demyelinating neuropathy. Cx32 is localized to the paranodes and incisures of myelinating Schwann cells, and probably participates in the formation of gap junctions at these locations, thereby allowing the diffusion of ions and small molecules directly across the myelin sheath. In transfected cells different CMTX mutations have different effects on the ability of the mutant protein to form functional gap junctions; some mutant proteins cannot be detected within the cell, other mutant proteins accumulate within the cell but do not reach the cell membrane, while other mutants reach the cell membrane and some of these form functional gap junctions. In transgenic mice two mutants, R142W and 175 frameshift, have similar effects on protein trafficking as in transfected cells: the R142W mutant protein remains in the perinuclear region and does not reach the paranodes or incisures, and the 175 frameshift protein cannot be detected. Thus, different CMTX mutations have different effects on Cx32 protein, and these differences may help to explain the phenotypic differences seen in CMTX kindreds.
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Affiliation(s)
- S S Scherer
- Department of Neurology, University of Pennsylvania School of Medicine, Philadelphia 19104, USA
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Deschênes SM, Walcott JL, Wexler TL, Scherer SS, Fischbeck KH. Altered trafficking of mutant connexin32. J Neurosci 1997; 17:9077-84. [PMID: 9364054 PMCID: PMC6573613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/1997] [Revised: 09/02/1997] [Accepted: 09/10/1997] [Indexed: 02/05/2023] Open
Abstract
We examined the cellular localization of nine different connexin32 (Cx32) mutants associated with X-linked Charcot-Marie-Tooth disease (CMTX) in communication-incompetent mammalian cells. Cx32 mRNA was made, but little or no protein was detected in one class of mutants. In another class of mutants, Cx32 protein was detectable in the cytoplasm and at the cell surface, where it appeared as plaques and punctate staining. Cx32 immunoreactivity in a third class of mutants was restricted to the cytoplasm, where it often colocalized with the Golgi apparatus. Our studies suggest that CMTX mutations have a predominant effect on the trafficking of Cx32 protein, resulting in a potentially toxic cytoplasmic accumulation of Cx32 in these cells. These results and evidence of cytoplasmic accumulation of other mutated myelin proteins suggest that diseases affecting myelinating cells may share a common pathophysiology.
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Affiliation(s)
- S M Deschênes
- Department of Neurology, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania 19104, USA
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9
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Abstract
Mutations in the gap junction gene connexin32 (Cx32) cause the X-linked form of Charcot-Marie-Tooth disease, an inherited demyelinating neuropathy. More than 130 different mutations have been described, affecting all portions of the Cx32 protein. In transfected cells, the mutant Cx32 proteins encoded by some Cx32 mutations fall to reach the cell surface; other mutant proteins reach the cell surface, but only one of these forms functional gap junctions. In peripheral nerve, Cx32 is localized to incisures and paranodes, regions of noncompact myelin within the myelin sheath. This localization suggests that Cx32 forms "reflexive" gap junctions that allow ions and small molecules to diffuse directly across the myelin sheath, which is a thousandfold shorter distance than the circumferential pathway through the Schwann cell cytoplasm. Cx32 mutations may interrupt this shorter pathway or have other toxic effects, thereby injuring myelinating Schwann cells and their axons.
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Affiliation(s)
- L J Bone
- Department of Neurology, University of Pennsylvania School of Medicine, Philadelphia 19104, USA
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Hoffman GR, Deschênes SM, Manyin T, Fuchs RP. Mutagenicity of acridines in a reversion assay based on tetracycline resistance in plasmid pBR322 in Escherichia coli. Mutat Res 1996; 351:33-43. [PMID: 8602172 DOI: 10.1016/0027-5107(95)00206-5] [Citation(s) in RCA: 18] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The mutagenicity of a series of acridine compounds was studied in an assay based on the reversion of mutations in the tetracycline-resistance gene (tet) of plasmid pBR322 in Escherichia coli. Mutations that restore the tetracycline-resistant phenotype were detected in tetracycline-sensitive strains carrying mutant plasmids. Mutations that revert by +2, +1, -1 and -2 frameshift mutations and by base-pair substitutions were used to analyze the mutagenicity of two simple acridines, two acridine mustards, and a nitroacridine. The simple acridines (9-aminoacridine and quinacrine) effectively induced -1 frameshifts and weakly induced +1 frameshifts. The acridine mustards (quinacrine mustard and ICR-191) were more potent inducers of -1 and +1 frameshifts than the simple acridines. Reactive acridines, including both the mustards and the nitroacridine Entozon, were effective inducers of -2 frameshifts but the simple acridines were not. The two classes of reactive acridines differed from one another, in that the mustards were better inducers of +1 frameshifts than Entozon, whereas Entozon was a particularly potent inducer of -2 frameshifts. None of the compounds induced +2 frameshifts, and the induction of base-pair substitutions was negligible. These results confirm and extend studies showing that adduct-forming acridines are stronger frameshift mutagens than simple intercalating acridines and that the acridines differ from one another not only in overall mutagenic potency but also in the prevalence of different classes of frameshift mutations.
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Affiliation(s)
- G R Hoffman
- Department of Biology, College of the Holy Cross, Worchester, MA 01610, USA
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Fischbeck KH, Deschênes SM, Bone LJ, Scherer SS. Connexin32 and X-linked Charcot-Marie-Tooth disease. Cold Spring Harb Symp Quant Biol 1996; 61:673-7. [PMID: 9246493] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- K H Fischbeck
- Neurology Department, University of Pennsylvania School of Medicine, Philadelphia 19104, USA
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Scherer SS, Deschênes SM, Xu YT, Grinspan JB, Fischbeck KH, Paul DL. Connexin32 is a myelin-related protein in the PNS and CNS. J Neurosci 1995; 15:8281-94. [PMID: 8613761 PMCID: PMC6577923] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We have examined the expression of a gap junction protein, connexin32 (Cx32), in Schwann cells and oligodendrocytes. In peripheral nerve, Cx32 is found in the paranodal myelin loops and Schmidt-Lanterman incisures of myelinating Schwann cells, and the levels of Cx32 protein and mRNA change in parallel with those of other myelin-related genes during development, Wallerian degeneration, and axonal regeneration. In the central nervous system, Cx32 is found in oligodendrocytes and their processes, but not in compact myelin, and the levels of Cx32 protein and mRNA increase during development in parallel with those of the other myelin genes. Thus, Cx32 is expressed as part of the myelinating phenotype of both Schwann cells and oligodendrocytes, indicating that this gap junction protein plays in important role in the biology of myelin-forming cells.
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Affiliation(s)
- S S Scherer
- Department of Neurology, University of Pennsylvania, Philadelphia 19104-6146, USA
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Deschênes SM, Puck JM, Dutra AS, Somberg RL, Felsburg PJ, Henthorn PS. Comparative mapping of canine and human proximal Xq and genetic analysis of canine X-linked severe combined immunodeficiency. Genomics 1994; 23:62-8. [PMID: 7829103 DOI: 10.1006/geno.1994.1459] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Parallel genetic analysis of animal and human genetic diseases can facilitate the identification and characterization of the causative gene defects. For example, canine X-linked severe combined immunodeficiency (SCID) is characterized by clinical, pathological, and immunological manifestations similar to the most common form of human SCID. To derive a canine syntenic map including genes that in humans are located in proximal Xq, near human X-linked SCID, poly(TG) polymorphisms were identified at the canine phosphoglycerate kinase (PGK) and choroideremia (CHM) loci. These plus a polymorphic poly(CAG) sequence in exon 1 of the canine androgen receptor gene (AR) were used to genotype members of the colony informative for X-linked SCID. No recombinations among SCIDX1, AR, PGK, or CHM were observed. Fluorescence in situ hybridization localized PGK and CHM to proximal Xq in the dog, in the same chromosomal location occupied by the human genes. Somatic cell hybrid analysis and methylation differences at AR demonstrated that female dogs carrying X-linked SCID have the same lymphocyte-limited skewed X-chromosome inactivation patterns as human carriers. These genetic and phenotypic findings provide evidence that mutations in the same gene, now identified as the gamma chain of the IL-2 receptor, cause canine and human X-linked SCID. This approach is an efficient method for comparative gene mapping and disease identification.
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Affiliation(s)
- S M Deschênes
- Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia
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Puck JM, Deschênes SM, Porter JC, Dutra AS, Brown CJ, Willard HF, Henthorn PS. The interleukin-2 receptor gamma chain maps to Xq13.1 and is mutated in X-linked severe combined immunodeficiency, SCIDX1. Hum Mol Genet 1993; 2:1099-104. [PMID: 8401490 DOI: 10.1093/hmg/2.8.1099] [Citation(s) in RCA: 202] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The gene encoding the gamma chain of the lymphocyte interleukin-2 receptor has been cloned and shown to be required to associate with the beta chain in order for IL-2 internalization and cell activation to occur (1). We considered this gene, IL2RG, a candidate for the X-linked form of severe combined immunodeficiency at the SCIDX1 locus, in which affected males have impaired lymphocyte development. Using fluorescence in situ hybridization and PCR amplification of somatic cell hybrid DNAs, we mapped IL2RG to human Xq13.1, a location within the SCIDX1 critical region established by linkage analysis. The 4.2 kb IL2RG gene was sequenced, and its genomic organization was elucidated. Seven of 19 transformed B-lymphocyte cell lines with independent SCIDX1 mutations had absent or minimal IL2RG mRNA. Unique point mutations were documented to be specifically associated with the disease and the carrier state in four unrelated affected males and their family members: one in a boy with no detectable IL2RG mRNA, in which the mutation ablated a splice donor site; one causing premature chain termination; and two causing distinct amino acid changes. The demonstration of impaired IL2RG mRNA expression in males with X-linked SCID and of unique point mutations in SCIDX1 pedigrees constitutes powerful evidence that the SCIDX1 gene is IL2RG. Noguchi et al. (2) have independently published IL2RG mapping to Xq13 and discovery of mutations in three affected males. The specific pathogenesis of IL2RG mutations and approaches to gene therapy can now be addressed in the X-linked form of SCID.
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Affiliation(s)
- J M Puck
- Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia 19104
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Deschênes SM. [Student enrollment in Canadian medical schools, 1976-77]. Can Med Assoc J 1977; 117:783-6. [PMID: 907951 PMCID: PMC1880066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The 1976-77 statistical study of medical school enrollment by the Association of Canadian Medical Colleges shows that total enrollment in Canadian medical schools had increased 103.8% since 1960-61, although the rate of increase had decreased to almost zero by 1976-77. Women accounted for 30.3% of the total enrollment in 1976-77 (for all years of the course), which represents an increase of more than 550% in the 17-year period; for the 16 schools the proportion ranged between 23.9% and 43.8%. Enrollment of foreign students had decreased from 340 in 1966-67 to 90 (1.2%) in 1976-77; 71 of the 90 students were American. For the entire nation the mean number of medical students per 10 000 population was 3.1, but in British Columbia the figure was only 1.5. Of the Canadian and landed immigrant students 94.5% were attending medical school in their home province.
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