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Papers by Mustapha Dibbasey

Research paper thumbnail of Additional file 1 of Laboratory indices of hospitalized sickle cell disease patients, prevalence and antimicrobial susceptibility of pathogenic bacterial isolates at MRCG ward in the Gambia

Research paper thumbnail of Prevalence and Antimicrobial Resistance Patterns of Pathogenic Bacterial Isolates of Hospitalized Sickle Cell Disease Patients Admitted in Our Tertiary Hospital in the Gambia

Research paper thumbnail of Introducing Novel Molecular-based Method for Quantification of Homologous Recombination Efficiency

bioRxiv (Cold Spring Harbor Laboratory), Jan 19, 2021

Background: Homologous recombination (HR) pathway is a DNA double-stranded breaks repair pathway ... more Background: Homologous recombination (HR) pathway is a DNA double-stranded breaks repair pathway well-known for its high level of accuracy. Low HR pathway efficiency clinically known as homologous recombination deficiency (HRD) was identified in some cancers such as breast and ovarian cancers and studies have reported the sensitivity of HRD cancer cells to DNA repair inhibitors such as Olaparib. However, current techniques including immunofluorescence-based technique are qualitative-based, hence lack sensitivity to determine the functionality of HR pathway. Additionally, some of the techniques including gene expression arrays require expression study of wide range genes involve in HR pathway, which is not cost-effective. The aim of the study is to optimise a PCR-based assay (Norgen's Homologous Recombination kit) that can be employed to quantitate HR efficiency in cells, which accurately reflects the functional status of HR pathway. Methods and Findings: The kit has two test plasmids (dl-1 and dl-2) with partial deletions in the LacZ gene and the plasmids are generated from modification of pUC19. HR-proficient (HeLa and AsPC-1) and HR-deficient (CAPAN-1 cells) cancer cell lines were transfected with the two plasmids to generate functional LacZ gene (i.e. recombinant product). The recombinant product was quantified by real-time PCR. Although recombinant product was generated in all the cell lines, our real-time PCR demonstrated a high quantity of recombinant product in HeLa cell line whilst low quantity in CAPAN-1 and AsPC-1 cell lines. The quantity of recombinant product generated and quantified reflects HR pathway efficiency. Conclusion: Overall, the results have provided some evidence that the PCR-based kit can be suitably employed for quantification of HR efficiency provided appropriate transfection method and reagent are used. However, further study is required to confirm HR efficiency status of AsPC-1 cells to ascertain the low HR efficiency detected by the kit in these cells. .

Research paper thumbnail of Comparative and Stability Study of Glucose Concentrations Measured in both Sodium Fluoride and Serum Separator tubes

bioRxiv (Cold Spring Harbor Laboratory), Jan 19, 2021

Introduction: Sodium fluoride/potassium oxalate (NaF/KOx) tubes were once regarded as the gold-st... more Introduction: Sodium fluoride/potassium oxalate (NaF/KOx) tubes were once regarded as the gold-standard tubes for glucose analysis. Even though their ineffectiveness in immediately inhibiting glycolysis has been reported in several studies especially in the first 1-4hours, they are still used in our clinical Biochemistry laboratory for glucose measurement. However in its absence, only SSTs are employed for glucose measurement. Aim: To determine whether SSTs can replace NaF/KOx tubes for laboratory-based measurement of blood glucose and to assess the stability of glucose concentrations for 3 days period Methods: During the study period (1 March to 11 April, 2015), a total of 50 paired samples collected separately in NaF/KOx tubes and SSTs from healthy adult participants in the Gambia Adults Reference Intervals Study (GARIS) project were used as the project sample size. The samples were analysed within 2hours, and at 24hours, 42hours and 72hours time-points following blood collection and separation using Vitros 350 dry chemistry analyser. The GARIS samples were treated as clinical samples. Results: There was no significant difference in the mean glucose concentrations between the two tubes (Mean difference= 0.06mmol/L; P=0.38) recorded in the different timepoints. Using growth trajectory and mixed effects model, the study data showed no significant change in the glucose concentrations (p=0.25) for three days period. Conclusions: The study confirms that SSTs can produce similar glucose results when employed in the absence of NaF/KOx tubes. Besides, the glucose concentrations were stable in both tubes for three days when the samples were separated within two hours and refrigerated in 2-8°C.

Research paper thumbnail of Comparing Cell-Dyn Emerald 22 AL to Sysmex XN-1500 automated haematology analyser for full blood count estimation

Introduction Modern haematology analysers provide an easy approach for enumerating the cellular c... more Introduction Modern haematology analysers provide an easy approach for enumerating the cellular components of blood in automated manner with improved turn-around-time. In our haematology laboratory, we have existing full blood count analyser, Sysmex XN-1500. We recently bought a backup full blood count analyser from Abbott Diagnostic, Cell Dyn Emerald 22 AL that enumerates cellular blood components using relatively similar measuring principles. As part of the method verification procedure required by ISO15189, we compared our newly purchased Cell Dyn Emerald 22 AL full blood count analyser to the existing verified Sysmex XN-1500 full blood count analyser. We further assessed the precision of both full blood count analysers. The residual EDTA blood samples were analysed using Sysmex XN-1500 (Sysmex Company Limited, Germany) as the reference analysers and CD Emerald 22 AL (Abbott, Abbott Park, Illinois, U.S.A) as newly purchased analysers. Method and Results We processed 120 residual ...

Research paper thumbnail of PB2502: Prevalence and Antimicrobial Susceptibility Pattern of Bacterial Pathogens Isolated from Sickle Cell Patients Admitted at MRCG Ward from 2015 to 2022

Research paper thumbnail of Laboratory indices of hospitalized Sickle Cell Disease Patients, Prevalence and Antimicrobial Susceptibility of pathogenic bacterial isolates at MRCG Ward in the Gambia

Research Square (Research Square), Apr 3, 2023

Research paper thumbnail of Prevalence of Iron Deficiency, Iron Deficiency Anaemia and General Anaemia in Male Gambian Blood Donors Residing in Greater Banjul Region

Objective: The objective of this study is to determine the prevalence of iron deficiency (ID) and... more Objective: The objective of this study is to determine the prevalence of iron deficiency (ID) and iron deficiency anaemia (IDA) as well as general anaemia in male blood donors and their association with ageing process. Methodology and Results: A total of two hundred and one (201) serum samples were analysed for ferritin in male Gambian blood donors. The ferritin measurement was achieved with COBAS INTEGRA 400 plus. At the same time, haemoglobin values were retrospectively obtained from the archived haematological full blood count result in the GARIS database. IDA was defined as (Haemoglobin <13.0g/dL+ Ferritin<15ng/ml) whilst ID was defined as (Haemoglobin >/=13.0g/dL+ Ferritin<15ng/ml) and general anaemia was defined as haemoglobin <13.0g/dL in males. The prevalence of anaemia (20%, n=41), ID (22%, n=44) and IDA (10%, n=21), were recorded in male donors. The results show no relationship between ferritin and haemoglobin among the blood donors (collection coefficient (...

Research paper thumbnail of Introducing Novel Molecular-based Method for Quantification of Homologous Recombination Efficiency

BackgroundHomologous recombination (HR) pathway is a DNA double-stranded breaks repair pathway we... more BackgroundHomologous recombination (HR) pathway is a DNA double-stranded breaks repair pathway well-known for its high level of accuracy. Low HR pathway efficiency clinically known as homologous recombination deficiency (HRD) was identified in some cancers such as breast and ovarian cancers and studies have reported the sensitivity of HRD cancer cells to DNA repair inhibitors such as Olaparib. However, current techniques including immunofluorescence-based technique are qualitative-based, hence lack sensitivity to determine the functionality of HR pathway. Additionally, some of the techniques including gene expression arrays require expression study of wide range genes involve in HR pathway, which is not cost-effective. The aim of the study is to optimise a PCR-based assay (Norgen’s Homologous Recombination kit) that can be employed to quantitate HR efficiency in cells, which accurately reflects the functional status of HR pathway.Methods and FindingsThe kit has two test plasmids (dl...

Research paper thumbnail of Comparative and Stability Study of Glucose Concentrations Measured in both Sodium Fluoride and Serum Separator tubes

Introduction Sodium fluoride/potassium oxalate (NaF/KOx) tubes were once regarded as the gold-sta... more Introduction Sodium fluoride/potassium oxalate (NaF/KOx) tubes were once regarded as the gold-standard tubes for glucose analysis. Even though their ineffectiveness in immediately inhibiting glycolysis has been reported in several studies especially in the first 1–4hours, they are still used in our clinical Biochemistry laboratory for glucose measurement. However in its absence, only SSTs are employed for glucose measurement. Aim To determine whether SSTs can replace NaF/KOx tubes for laboratory-based measurement of blood glucose and to assess the stability of glucose concentrations for 3 days period Methods During the study period (1 March to 11 April, 2015), a total of 50 paired samples collected separately in NaF/KOx tubes and SSTs from healthy adult participants in the Gambia Adults Reference Intervals Study (GARIS) project were used as the project sample size. The samples were analysed within 2hours, and at 24hours, 42hours and 72hours time-points following blood collection and...

Research paper thumbnail of Additional file 1 of Laboratory indices of hospitalized sickle cell disease patients, prevalence and antimicrobial susceptibility of pathogenic bacterial isolates at MRCG ward in the Gambia

Research paper thumbnail of Prevalence and Antimicrobial Resistance Patterns of Pathogenic Bacterial Isolates of Hospitalized Sickle Cell Disease Patients Admitted in Our Tertiary Hospital in the Gambia

Research paper thumbnail of Introducing Novel Molecular-based Method for Quantification of Homologous Recombination Efficiency

bioRxiv (Cold Spring Harbor Laboratory), Jan 19, 2021

Background: Homologous recombination (HR) pathway is a DNA double-stranded breaks repair pathway ... more Background: Homologous recombination (HR) pathway is a DNA double-stranded breaks repair pathway well-known for its high level of accuracy. Low HR pathway efficiency clinically known as homologous recombination deficiency (HRD) was identified in some cancers such as breast and ovarian cancers and studies have reported the sensitivity of HRD cancer cells to DNA repair inhibitors such as Olaparib. However, current techniques including immunofluorescence-based technique are qualitative-based, hence lack sensitivity to determine the functionality of HR pathway. Additionally, some of the techniques including gene expression arrays require expression study of wide range genes involve in HR pathway, which is not cost-effective. The aim of the study is to optimise a PCR-based assay (Norgen's Homologous Recombination kit) that can be employed to quantitate HR efficiency in cells, which accurately reflects the functional status of HR pathway. Methods and Findings: The kit has two test plasmids (dl-1 and dl-2) with partial deletions in the LacZ gene and the plasmids are generated from modification of pUC19. HR-proficient (HeLa and AsPC-1) and HR-deficient (CAPAN-1 cells) cancer cell lines were transfected with the two plasmids to generate functional LacZ gene (i.e. recombinant product). The recombinant product was quantified by real-time PCR. Although recombinant product was generated in all the cell lines, our real-time PCR demonstrated a high quantity of recombinant product in HeLa cell line whilst low quantity in CAPAN-1 and AsPC-1 cell lines. The quantity of recombinant product generated and quantified reflects HR pathway efficiency. Conclusion: Overall, the results have provided some evidence that the PCR-based kit can be suitably employed for quantification of HR efficiency provided appropriate transfection method and reagent are used. However, further study is required to confirm HR efficiency status of AsPC-1 cells to ascertain the low HR efficiency detected by the kit in these cells. .

Research paper thumbnail of Comparative and Stability Study of Glucose Concentrations Measured in both Sodium Fluoride and Serum Separator tubes

bioRxiv (Cold Spring Harbor Laboratory), Jan 19, 2021

Introduction: Sodium fluoride/potassium oxalate (NaF/KOx) tubes were once regarded as the gold-st... more Introduction: Sodium fluoride/potassium oxalate (NaF/KOx) tubes were once regarded as the gold-standard tubes for glucose analysis. Even though their ineffectiveness in immediately inhibiting glycolysis has been reported in several studies especially in the first 1-4hours, they are still used in our clinical Biochemistry laboratory for glucose measurement. However in its absence, only SSTs are employed for glucose measurement. Aim: To determine whether SSTs can replace NaF/KOx tubes for laboratory-based measurement of blood glucose and to assess the stability of glucose concentrations for 3 days period Methods: During the study period (1 March to 11 April, 2015), a total of 50 paired samples collected separately in NaF/KOx tubes and SSTs from healthy adult participants in the Gambia Adults Reference Intervals Study (GARIS) project were used as the project sample size. The samples were analysed within 2hours, and at 24hours, 42hours and 72hours time-points following blood collection and separation using Vitros 350 dry chemistry analyser. The GARIS samples were treated as clinical samples. Results: There was no significant difference in the mean glucose concentrations between the two tubes (Mean difference= 0.06mmol/L; P=0.38) recorded in the different timepoints. Using growth trajectory and mixed effects model, the study data showed no significant change in the glucose concentrations (p=0.25) for three days period. Conclusions: The study confirms that SSTs can produce similar glucose results when employed in the absence of NaF/KOx tubes. Besides, the glucose concentrations were stable in both tubes for three days when the samples were separated within two hours and refrigerated in 2-8°C.

Research paper thumbnail of Comparing Cell-Dyn Emerald 22 AL to Sysmex XN-1500 automated haematology analyser for full blood count estimation

Introduction Modern haematology analysers provide an easy approach for enumerating the cellular c... more Introduction Modern haematology analysers provide an easy approach for enumerating the cellular components of blood in automated manner with improved turn-around-time. In our haematology laboratory, we have existing full blood count analyser, Sysmex XN-1500. We recently bought a backup full blood count analyser from Abbott Diagnostic, Cell Dyn Emerald 22 AL that enumerates cellular blood components using relatively similar measuring principles. As part of the method verification procedure required by ISO15189, we compared our newly purchased Cell Dyn Emerald 22 AL full blood count analyser to the existing verified Sysmex XN-1500 full blood count analyser. We further assessed the precision of both full blood count analysers. The residual EDTA blood samples were analysed using Sysmex XN-1500 (Sysmex Company Limited, Germany) as the reference analysers and CD Emerald 22 AL (Abbott, Abbott Park, Illinois, U.S.A) as newly purchased analysers. Method and Results We processed 120 residual ...

Research paper thumbnail of PB2502: Prevalence and Antimicrobial Susceptibility Pattern of Bacterial Pathogens Isolated from Sickle Cell Patients Admitted at MRCG Ward from 2015 to 2022

Research paper thumbnail of Laboratory indices of hospitalized Sickle Cell Disease Patients, Prevalence and Antimicrobial Susceptibility of pathogenic bacterial isolates at MRCG Ward in the Gambia

Research Square (Research Square), Apr 3, 2023

Research paper thumbnail of Prevalence of Iron Deficiency, Iron Deficiency Anaemia and General Anaemia in Male Gambian Blood Donors Residing in Greater Banjul Region

Objective: The objective of this study is to determine the prevalence of iron deficiency (ID) and... more Objective: The objective of this study is to determine the prevalence of iron deficiency (ID) and iron deficiency anaemia (IDA) as well as general anaemia in male blood donors and their association with ageing process. Methodology and Results: A total of two hundred and one (201) serum samples were analysed for ferritin in male Gambian blood donors. The ferritin measurement was achieved with COBAS INTEGRA 400 plus. At the same time, haemoglobin values were retrospectively obtained from the archived haematological full blood count result in the GARIS database. IDA was defined as (Haemoglobin <13.0g/dL+ Ferritin<15ng/ml) whilst ID was defined as (Haemoglobin >/=13.0g/dL+ Ferritin<15ng/ml) and general anaemia was defined as haemoglobin <13.0g/dL in males. The prevalence of anaemia (20%, n=41), ID (22%, n=44) and IDA (10%, n=21), were recorded in male donors. The results show no relationship between ferritin and haemoglobin among the blood donors (collection coefficient (...

Research paper thumbnail of Introducing Novel Molecular-based Method for Quantification of Homologous Recombination Efficiency

BackgroundHomologous recombination (HR) pathway is a DNA double-stranded breaks repair pathway we... more BackgroundHomologous recombination (HR) pathway is a DNA double-stranded breaks repair pathway well-known for its high level of accuracy. Low HR pathway efficiency clinically known as homologous recombination deficiency (HRD) was identified in some cancers such as breast and ovarian cancers and studies have reported the sensitivity of HRD cancer cells to DNA repair inhibitors such as Olaparib. However, current techniques including immunofluorescence-based technique are qualitative-based, hence lack sensitivity to determine the functionality of HR pathway. Additionally, some of the techniques including gene expression arrays require expression study of wide range genes involve in HR pathway, which is not cost-effective. The aim of the study is to optimise a PCR-based assay (Norgen’s Homologous Recombination kit) that can be employed to quantitate HR efficiency in cells, which accurately reflects the functional status of HR pathway.Methods and FindingsThe kit has two test plasmids (dl...

Research paper thumbnail of Comparative and Stability Study of Glucose Concentrations Measured in both Sodium Fluoride and Serum Separator tubes

Introduction Sodium fluoride/potassium oxalate (NaF/KOx) tubes were once regarded as the gold-sta... more Introduction Sodium fluoride/potassium oxalate (NaF/KOx) tubes were once regarded as the gold-standard tubes for glucose analysis. Even though their ineffectiveness in immediately inhibiting glycolysis has been reported in several studies especially in the first 1–4hours, they are still used in our clinical Biochemistry laboratory for glucose measurement. However in its absence, only SSTs are employed for glucose measurement. Aim To determine whether SSTs can replace NaF/KOx tubes for laboratory-based measurement of blood glucose and to assess the stability of glucose concentrations for 3 days period Methods During the study period (1 March to 11 April, 2015), a total of 50 paired samples collected separately in NaF/KOx tubes and SSTs from healthy adult participants in the Gambia Adults Reference Intervals Study (GARIS) project were used as the project sample size. The samples were analysed within 2hours, and at 24hours, 42hours and 72hours time-points following blood collection and...