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Tamambang R, Kusi-Mensah K, Bella-Awusah T, Ogunmola O, Afolayan A, Toska E, Hertzog L, Rudgard W, Evans R, Omigbodun O. Identifying potential catalysts to accelerate the achievement of Sustainable Development Goals (SDGs) among adolescents living in Nigeria. PSYCHOL HEALTH MED 2024; 29:868-887. [PMID: 38305209 DOI: 10.1080/13548506.2023.2289476] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Accepted: 11/22/2023] [Indexed: 02/03/2024]
Abstract
Investing in adolescents in Africa holds great promise for the development of the continent. The steps involved in identifying factors linked to interventions that may accelerate the attainment of multiple SDGs for adolescents in Nigeria are described. Data from a survey to investigate the well-being of 1800 adolescents aged 10-19 years in Southwest Nigeria was analysed. A four-step process was employed: 1) Mapping of variables deemed as suitable proxies for SDG targets; 2) Mapping hypothesised protective factors (accelerators) from the study instruments. Consequently, SDG targets related to elimination of hunger, good health, gender equality and peace; and seven accelerators (safe schools, parenting support, good mental health, no survival work, food security, stable childhood, and regular physical activity) were identified; 3) evaluating associations using bivariate analysis and multivariable logistic regression, 4) calculating adjusted probabilities. The mean age of the adolescents was 15.02 ± 2.27 years (48.6% female). Good mental health, not doing survival work, safe schools, stable childhood and parental support were significantly associated with at least two SDG targets. For example, food security was significantly associated with the highest number of SDG outcomes: one SDG target related to child survival (no substance use: x2 = 3.39, p = <0.001); three SDG targets related to educational outcomes (school progression: x2 = 5.68, p = 0.017, ability to concentrate in school: x2 = 26.92, p = <0.001, and school attendance: x2 = 25.89, p = <0.001); and four SDG targets related to child protection (no risky sexual behaviours: x2 = 16.14, p = <0.001, no perpetration of violence: x2 = 15.74, p = <0.001, no community violence: x2 = 39.06, p =<0.001, and no sexual abuse: x2 = 7.66, p = 0.006). Interventions centred around good mental health, not doing survival work, safe schools, small family size, stable childhood and parental support are potential accelerators for the attainment of SDG outcomes by adolescents living in Nigeria.
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Affiliation(s)
- Rita Tamambang
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Kwabena Kusi-Mensah
- Department of Psychiatry, University of Cambridge, Cambridge, UK
- Department of Psychiatry, Komfo Anokye Teaching Hospital, Kumasi, Ghana
| | - Tolulope Bella-Awusah
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Olusegun Ogunmola
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Adeola Afolayan
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Elona Toska
- Centre for Social Science Research, University of Cape Town, Cape Town, South Africa
- Department of Social Policy and Intervention, Oxford University, Oxford, UK
| | - Lucas Hertzog
- Centre for Social Science Research, University of Cape Town, Cape Town, South Africa
| | | | - Robin Evans
- Department of Statistics, Oxford University, Oxford, UK
| | - Olayinka Omigbodun
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
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Bella-Awusah T, Abdurahman H, Omobowale O, Aturu O, Afolayan A, Ogunmola O, Fasoranti B, Olusanmi M, Tamambang R, Bamidele O, Ryan G, Shakespeare T, Eaton J, Omigbodun O. Lessons of Hope and Resilience: A Co-Produced Qualitative Study of the Experiences of Youth Living with Psychosis During the COVID-19 Pandemic in Nigeria. Community Ment Health J 2024; 60:47-59. [PMID: 37306804 PMCID: PMC10258758 DOI: 10.1007/s10597-023-01128-8] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Accepted: 04/13/2023] [Indexed: 06/13/2023]
Abstract
Much of the emerging evidence on the impact of COVID-19 on people with psychosocial disabilities comes from high-income countries. This study sought to explore the perceptions and experiences of youths living with psychosis during the COVID-19 pandemic in Nigeria. Using a co-produced research process, a facility-based study was conducted among youth with confirmed diagnosis of a psychotic disorder. In-depth interviews were conducted with 20 participants. Data was transcribed, double-coded and analysed with Atlas.ti using a thematic analysis approach. We found that participants were aware of good evidence-based information on the nature of the disease and the pandemic. Many of them described worsening mental health and disruptions to daily routines. Opportunities for deepening family relationships, skill building, helping others, and extended time for previously neglected self-development activities were described. This study benefitted from co-production with persons with lived experience, which could be harnessed for future research on psychosis.
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Affiliation(s)
- Tolulope Bella-Awusah
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
- Department of Child and Adolescent Psychiatry, University College Hospital, Ibadan, Nigeria
- Department of Psychiatry, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Haleem Abdurahman
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
- Department of Child and Adolescent Psychiatry, University College Hospital, Ibadan, Nigeria
| | - Olubukola Omobowale
- Rehabilitative and Social Medicine Unit, Department of Community Medicine, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Olayinka Aturu
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Adeola Afolayan
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Olusegun Ogunmola
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Bisola Fasoranti
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Mayowa Olusanmi
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Rita Tamambang
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Olayinka Bamidele
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Grace Ryan
- Centre for Global Mental Health, London School of Hygiene and Tropical Medicine, London, UK
| | - Thomas Shakespeare
- Centre for Global Mental Health, London School of Hygiene and Tropical Medicine, London, UK
| | - Julian Eaton
- Centre for Global Mental Health, London School of Hygiene and Tropical Medicine, London, UK
- CBM Global Disability and Inclusion, Laudenbach, Germany
| | - Olayinka Omigbodun
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria.
- Department of Child and Adolescent Psychiatry, University College Hospital, Ibadan, Nigeria.
- Department of Psychiatry, College of Medicine, University of Ibadan, Ibadan, Nigeria.
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Jakobsson CE, Genovesi E, Afolayan A, Bella-Awusah T, Omobowale O, Buyanga M, Kakuma R, Ryan GK. Co-producing research on psychosis: a scoping review on barriers, facilitators and outcomes. Int J Ment Health Syst 2023; 17:25. [PMID: 37644476 PMCID: PMC10466887 DOI: 10.1186/s13033-023-00594-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Accepted: 07/31/2023] [Indexed: 08/31/2023] Open
Abstract
INTRODUCTION Co-production is a collaborative approach to service user involvement in which users and researchers share power and responsibility in the research process. Although previous reviews have investigated co-production in mental health research, these do not typically focus on psychosis or severe mental health conditions. Meanwhile, people with psychosis may be under-represented in co-production efforts. This scoping review aims to explore the peer-reviewed literature to better understand the processes and terminology employed, as well as the barriers, facilitators, and outcomes of co-production in psychosis research. METHODS Three databases were searched (MEDLINE, EMBASE, PsycINFO) using terms and headings related to psychosis and co-production. All titles, abstracts and full texts were independently double-screened. Disagreements were resolved by consensus. Original research articles reporting on processes and methods of co-production involving adults with psychosis as well as barriers, facilitators, and/or outcomes of co-production were included. Data was extracted using a standardised template and synthesised narratively. Joanna Briggs Institute and the AGREE Reporting Checklist were used for quality assessment. RESULTS The search returned 1243 references. Fifteen studies were included: five qualitative, two cross-sectional, and eight descriptive studies. Most studies took place in the UK, and all reported user involvement in the research process; however, the amount and methods of involvement varied greatly. Although all studies were required to satisfy INVOLVE (2018) principles of co-production to be included, seven were missing several of the key features of co-production and often used different terms to describe their collaborative approaches. Commonly reported outcomes included improvements in mutual engagement as well as depth of understanding and exploration. Key barriers were power differentials between researchers and service users and stigma. Key facilitators were stakeholder buy-in and effective communication. CONCLUSIONS The methodology, terminology and quality of the studies varied considerably; meanwhile, over-representation of UK studies suggests there may be even more heterogeneity in the global literature not captured by our review. This study makes recommendations for encouraging co-production and improving the reporting of co-produced research, while also identifying several limitations that could be improved upon for a more comprehensive review of the literature.
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Affiliation(s)
- C E Jakobsson
- Department of Psychiatry, Sussex Partnership NHS Foundation Trust, Eastbourne, England, UK.
| | - E Genovesi
- Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, England, UK
| | - A Afolayan
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - T Bella-Awusah
- Department of Psychiatry & Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - O Omobowale
- Department of Community Medicine, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - M Buyanga
- SUCCEED Africa, University of Zimbabwe, Harare, Zimbabwe
| | - R Kakuma
- London School of Hygiene and Tropical Medicine, Centre for Global Mental Health, London, England, UK.
| | - G K Ryan
- London School of Hygiene and Tropical Medicine, Centre for Global Mental Health, London, England, UK.
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Mellouki A, Ziba O, Gebreselassie K, Nedjim S, Afolayan A, Traore Y, Kirakoya B, Ouattara A, Kaboré F, Mellas S, El Ammari J, Tazi M, El Fassi M, Kura M, Farih M. The management of adult male anterior urethral strictures in low and middle income countries. Results from a Pan-African survey on male anterior urethral stricture management among urologists (PASUSM). Eur Urol 2023. [DOI: 10.1016/s0302-2838(23)00491-8] [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: 02/12/2023]
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Kusi-Mensah K, Tamambang R, Bella-Awusah T, Ogunmola S, Afolayan A, Toska E, Hertzog L, Rudgard W, Evans R, Omigbodun O. Accelerating progress towards the sustainable development goals for adolescents in Ghana: a cross-sectional study. PSYCHOL HEALTH MED 2022; 27:49-66. [PMID: 35957619 DOI: 10.1080/13548506.2022.2108086] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Since the adoption of the sustainable development goals (SDGs) by the United Nations (UN), the search has been on to identify interventions that have effects on multiple SDG-targets simultaneously. Like other developing countries, Ghana has a youthful population and would require creative, urgent, youth-focused interventions to be able to attain the SDGs by 2030. This paper describes the application of the accelerator model on data from a sample of Ghanaian adolescents to identify potential accelerators towards selected SDG targets involving youth. The data for 944 adolescents, 10-19 years (mean age 12.31 ± 3.51 years), extracted from two cross-sectional surveys on children and adolescents aged 6-19 years in Kumasi, Ghana, were analysed in this paper. Variables considered suitable proxies for SDG targets and potential accelerators were identified from the study instruments. Consequently, four aligned SDG targets (good mental health, access to ICT, school completion and no open defaecation) and five accelerators (cognitive stimulation, no relative poverty, low student-teacher ratio, high caregiver education and safe water) were extracted. Associations between accelerators and SDG targets were assessed using multivariable logistic regression adjusting for sociodemographic covariates and multiple testing. Cumulative effects were tested by marginal effects modelling. The three hypothesised accelerators identified were cognitive stimulation, low student-teacher ratio, and no relative poverty. A combination of all three accelerators was associated with a higher likelihood of adolescents having access to Information and Communication Technology (ICT) by +73% (CI 0.72-0.74), no open defecation by +44% (CI 0.43-0.46), school completion by +27% (CI 0.26-0.27) and good mental health by +9% (CI 0.08-0.10). Three hypothesized accelerators showed association across all four SDG aligned targets. The accelerator model has been further validated in this dataset from Ghana. Robust interventions designed around these accelerators may represent an opportunity for achieving the SDGs in Ghana.
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Affiliation(s)
- Kwabena Kusi-Mensah
- Department of Psychiatry, University of Cambridge, Clifford Allbutt Building, Cambridge, UK.,Komfo Anokye Teaching Hospital Kumasi, Ghana
| | - Rita Tamambang
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Tolulope Bella-Awusah
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Segun Ogunmola
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Adeola Afolayan
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Elona Toska
- Centre for Social Science Research, University of Cape Town, Cape Town, South Africa.,Department of Social Policy and Intervention, Oxford University, Oxford, UK
| | - Lucas Hertzog
- Centre for Social Science Research, University of Cape Town, Cape Town, South Africa
| | | | - Robin Evans
- Department of Statistics, Oxford University, Oxford, UK
| | - Olayinka Omigbodun
- Centre for Child and Adolescent Mental Health, College of Medicine, University of Ibadan, Ibadan, Nigeria
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Adeyemi O, Osilesi O, Adebawo O, Onajobi F, Oyedemi S, Afolayan A. Effect of processed Atlantic horse mackerel (
Trachurus trachurus
) on some hematological indices and enzyme activities in selected rat tissues (1044.2). FASEB J 2014. [DOI: 10.1096/fasebj.28.1_supplement.1044.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - O. Osilesi
- BiochemistryBabcock University Ilisan RemoOgun StateNigeria
| | - O. Adebawo
- BiochemistryBabcock University Ilisan RemoOgun StateNigeria
| | - F. Onajobi
- BiochemistryBabcock University Ilisan RemoOgun StateNigeria
| | - S Oyedemi
- Botany University of Fort Hare AliceEastern CapeSouth Africa
| | - A Afolayan
- Botany University of Fort Hare AliceEastern CapeSouth Africa
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Abstract
Glucose 6-phosphate dehydrogenase (G6PD) is a cytosolic enzyme encoded by a housekeeping X-linked gene whose main function is to produce NADPH, a key electron donor in the defense against oxidizing agents and in reductive biosynthetic reactions. Inherited G6PD deficiency is associated with either episodic hemolytic anemia (triggered by fava beans or other agents) or life-long hemolytic anemia. We show here that an evolutionary analysis is a key to understanding the biology of a housekeeping gene. From the alignment of the amino acid (aa) sequence of 52 glucose 6-phosphate dehydrogenase (G6PD) species from 42 different organisms, we found a striking correlation between the aa replacements that cause G6PD deficiency in humans and the sequence conservation of G6PD: two-thirds of such replacements are in highly and moderately conserved (50-99%) aa; relatively few are in fully conserved aa (where they might be lethal) or in poorly conserved aa, where presumably they simply would not cause G6PD deficiency. This is consistent with the notion that all human mutants have residual enzyme activity and that null mutations are lethal at some stage of development. Comparing the distribution of mutations in a human housekeeping gene with evolutionary conservation is a useful tool for pinpointing amino acid residues important for the stability or the function of the corresponding protein. In view of the current explosive increase in full genome sequencing projects, this tool will become rapidly available for numerous other genes.
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Affiliation(s)
- R Notaro
- Department of Human Genetics, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA
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Ajele JO, Afolayan A. Purification and characterisation of glutathione transferase from the giant African snail, Archachatina marginata. Comp Biochem Physiol B 1992; 103:47-55. [PMID: 1451443 DOI: 10.1016/0305-0491(92)90412-k] [Citation(s) in RCA: 4] [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] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
1. Glutathione-S-transferase has been purified from the hepatopancreas of Archachatina marginata to homogeneity. 2. The enzyme was found to be a dimer with a molecular weight of 44,000. The subunits sizes were 22,500 and 23,500 respectively. The isoelectric points of the enzyme were 8.35, 7.95 and 4. The enzyme was most stable at temperature below 40 degrees C. Upon denaturation by 4 M urea, only 56% of the activity could be recovered. 3. The Kms for glutathione and 1-chloro-2,4-dinitrobenze (CDNB) were 0.23 mM and 0.4 mM respectively. The specific activity of the enzyme with CDNB and p-nitrophylacetate as substrates were 47 mumol/mg and 38 mumol/mg respectively. 4. Inhibition studies showed that S-hexylglutathione, Rose Bengal, iodoacetamide, sodium azide and Procion Blue H-B were good inhibitors with I50 values ranging from 18.5 microM to 299 mM. 5. The amino acid composition showed that the enzyme had a relatively high content of hydrophobic and acidic amino acid residues. The peptide maps of the tryptic digests of the native and performic acid-oxidised enzyme indicated that there might be about two disulphide bridges per molecule of the enzyme.
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Affiliation(s)
- J O Ajele
- Department of Biochemistry, Federal University of Technology, Akure, Nigeria
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Afolayan A, Daini OA. Isolation and properties of creatine kinase from the breast muscle of tropical fruit bat, Eidolon helvum (Kerr). Comp Biochem Physiol B 1986; 85:463-8. [PMID: 3780189 DOI: 10.1016/0305-0491(86)90028-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Creatine kinase, from fruit bat breast muscle, has been purified to homogeneity. The mol. wt of the enzyme was estimated to be about 78,000-80,000 with two subunits of 42,500. There are nine thiol residues/mol of the enzyme and two of these react readily with DTNB leading to total inactivation of the enzyme. The metal ion specificity was in order Mg2+ greater than Zn2+ greater than Co2+. Initial velocity and product inhibition studies of the reverse reaction are consistent with sequential reaction but of either rapid equilibrium random or ordered type.
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Levy HR, Ingulli J, Afolayan A. Identification of essential arginine residues in glucose-6-phosphate dehydrogenase from Leuconostoc mesenteroides. J Biol Chem 1977; 252:3745-51. [PMID: 16915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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Luzzatto L, Afolayan A. Genetic variants of human erythrocyte glucose 6-phosphate dehydrogenase. II. In vitro and in vivo function of the A- variant. Biochemistry 1971; 10:420-3. [PMID: 5543968 DOI: 10.1021/bi00779a010] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Afolayan A, Luzzatto L. Genetic variants of human erythrocyte glucose 6-phosphate dehydrogenase. I. Regulation of activity by oxidized and reduced nicotinamide-adenine dinucleotide phosphate. Biochemistry 1971; 10:415-9. [PMID: 5543967 DOI: 10.1021/bi00779a009] [Citation(s) in RCA: 40] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Luzzatto L, Afolayan A. Enzymic properties of different types of human erythrocyte glucose-6-phosphate dehydrogenase, with characterization of two new genetic variants. J Clin Invest 1968; 47:1833-42. [PMID: 5666113 PMCID: PMC297343 DOI: 10.1172/jci105873] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Enzymic properties have been compared in the following five genetic variants of glucose-6-phosphate dehydrogenase from human erythrocytes: the two common variants with normal activity, A and B; the common variant associated with enzyme deficiency, A-; and two new rare variants, "Ijebu-Ode" and "Ita-Bale."The maximal velocity of the enzyme reaction (V(max)) increases steadily with pH over the entire range explored (from pH 5.5 to 9.5) for all enzyme variants when buffers are used that show no specific ion effects on enzyme activity. Small differences are found among the variants in the pH range 7.5-8.2, where A and B show a "peak and trough," while A-, "Ijebu-Ode," and "Ita-Bale" exhibit a plateau. When the effects of reagents that bind to sulphydryl groups are compared, iodoacetate, bromoacetate, and iodoacetamide are weak inhibitors, while N-ethylmaleimide (NEM) and hydroxymercuribenzoate (HMB) are potent inhibitors. The last two reagents have differential inhibitory action on different variants; one of these, "Ijebu-Ode," is strikingly resistant to HMB and totally resistant to NEM (up to 3 mmoles/liter). The enzyme inactivation as a function of temperature exhibits distinctive profiles for all variants examined. BOTH OF THE NEW VARIANTS DESCRIBED DIFFER SIGNIFICANTLY FROM THE NORMAL B TYPE IN SEVERAL RESPECTS: "Ijebu-Ode" in electrophoretic mobility, thermostability, dependence of V(max) on pH, and resistance to sulphydryl group reagents; "Ita-Bale" in electrophoretic mobility, Michaelis constant (K(m)) for glucose-6-phosphate, and dependence of V(max) on pH. When these data are compared with those available in the literature, both variants are different from all those previously described. The estimated frequencies of the corresponding genes in western Nigeria are between 0.0005 and 0.0025 for "Ijebu-Ode" and less than 0.0005 for "Ita-Bale". The A- variant, compared to A, has a distinctly higher K(m) for 2-deoxyglucose-6-phosphate and is more inhibited by very low concentrations of HMB. These are the first observed differences in kinetic properties between A and A-.
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