The Experts below are selected from a list of 150 Experts worldwide ranked by ideXlab platform
Shahin Fakhim - One of the best experts on this subject based on the ideXlab platform.
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Prevalence of occult hepatitis C virus infection in Iranian patients with Beta thalassemia major
Archives of Virology, 2016Co-Authors: Mohammad-navid Bastani, Farah Bokharaei-salim, Hossein Keyvani, Maryam Esghaei, Seyed Hamidreza Monavari, Mojtaba Ebrahimi, Saba Garshasebi, Shahin FakhimAbstract:Occult hepatitis C virus infection (OCI) is a new pathological form of chronic hepatitis virus (HCV) infection characterized by the presence of HCV RNA in liver biopsy and/or peripheral blood mononuclear cell (PBMC) specimens and the absence of HCV RNA and anti-HCV antibodies (Abs) in plasma samples. β-thalassemia major is a hereditary recessive blood disease with deficiency in the Hemoglobin Beta Chain. Thalassemic patients need blood transfusion therapy; repeated blood transfusion increases the risk of viral blood-borne infection. The aim of this study was to determine the prevalence of OCI in Iranian patients with β-thalassemia major. From February 2015 to November 2015, a total of 147 Iranian patients with β-thalassemia major were enrolled in this cross-sectional study. After extraction of viral RNA from the plasma and PBMC samples, HCV genomic RNA in the specimens was amplified by RT-nested PCR using primers from the 5′-UTR. The HCV genotypes of the positive specimens were tested using the RFLP assay. To confirm the HCV genotypes, the 5′-UTR fragment was amplified and cloned into the pJET1.2/blunt cloning vector and then sequenced. Out of 147 patients, 106 (72.1 %) were negative for anti-HCV Abs and HCV RNA. HCV RNA was found in PBMC specimens of six (5.7 %) patients, from a total of 106 patients with undetectable plasma HCV RNA and anti-HCV Abs. Therefore, six out of 106 patients had OCI. HCV genotyping revealed that three patients were infected with HCV subtype 1b, two patients were infected with HCV subtype 3a, and one patient was infected with HCV subtype 1a. These results revealed that Iranian patients with Beta-thalassemia major might have OCI. Therefore, it seems that the design of a study to identify this infection in patients with β-thalassemia major would provide valuable information.
Xiaoyun Fu - One of the best experts on this subject based on the ideXlab platform.
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cysteine 93 of Hemoglobin Beta Chain is the major target of oxidation during red blood cell storage
Blood, 2009Co-Authors: Grady R Blacken, Yi Wang, Jose A Lopez, Xiaoyun FuAbstract:Abstract 4040 Poster Board III-976 Red blood cells (RBC) stored for prolonged time periods under blood banking conditions are known to accumulate irreversible damage that ultimately affects their viability and function. Among the consequences of this RBC storage lesion are enhanced hemolysis and oxidative stress after transfusion. Stored RBCs accumulate reactive oxygen species (ROS) and surface-associated hemichrome, a partially denatured form of oxidized Hemoglobin. In this work, we examined whether the ROS created during RBC storage lead to characteristic oxidative modifications to Hemoglobin (Hb) and RBC membrane proteins. To characterize Hb modifications leading to hemichrome formation, we oxidized human Hemoglobin A with varied concentrations of hydrogen peroxide (H2O2), an oxidant relevant to RBC storage. The reaction was quenched with excess methionine and the protein digested with trypsin. The resulting peptides were analyzed by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). Methionine and cysteine residues are the major targets of oxidation. Oxidation of methionine to methionine sulfoxide and cysteine to cysteine sulfonic/sulfinic acids is accompanied by a mass shift related to the covalent modifications of each residue, which are readily detected by LC-ESI-MS/MS. We found that HBβ-Cys-93 was oxidized to a maximum of approximately 70% after treatment with 200 αM H2O2. This cysteine occurs adjacent to the FeII-coordinating His-92 and is thus exposed to the heme-FeII center. In contrast, HBβ-Cys-112 and HBα-Cys-104, which are buried and located away from the heme-FeII center, were oxidized to only 2% and 0%, respectively. The enhanced oxidation of the heme-FeII proximal HBβ-Cys-93 suggests that ROS are generated through a FeII-dependent mechanism such as Fenton9s reaction. Oxidation of each of the three Hb methionines reached 20% upon treatment with 200 μM H2O2. Among these Met residues, HBα-Met-32 is located near the heme-FeII, center, while both Hbα-Met-76 and HBβ-Met-55 are near the protein/solvent interface. Thus, Cys and Met oxidations in Hb appear to be dependent on proximity to either the heme-FeII center or the protein/solvent interface. To test whether these Hb residues are also sensitive to oxidation during storage we acquired 3 RBC units stored for 3 days and 3 RBC units stored for 45 days, from the Puget Sound Blood Center. The cytosolic Hb was extracted by hypotonic lysis and digested with trypsin prior to LC-ESI-MS/MS analysis. We observed that oxidation of HBβ-Cys-93 was dramatically increased from 10% on day 3 to 29% on day 45 (p Our observations suggest that HBβ-Cys-93 oxidation is a specific and sensitive marker for oxidative stress during storage. Moreover, we have correlated these progressive oxidations with increases in microvesiculation and hemolysis, storage-time-dependent changes that have been well documented. Future studies will evaluate the storage-time-dependence in other oxidative and post-translational modifications to RBC membrane proteins and correlate these findings with functional consequences such as microvesiculation and hemolysis. Disclosures: No relevant conflicts of interest to declare.
Mohammad-navid Bastani - One of the best experts on this subject based on the ideXlab platform.
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Detection of HCV genome in peripheral blood mononuclear cells of Iranian seropositive and HCV RNA negative in plasma of patients with Beta‐thalassemia major: Occult HCV infection
Journal of Medical Virology, 2018Co-Authors: Roya Kahyesh‐esfandiary, Mohammad-navid Bastani, Maryam Esghaei, Zohreh-azita Sadigh, Tahereh Donyavi, Alireza Najafi, Atousa Fakhim, Farah Bokharaei-salimAbstract:: Beta (β) thalassemia major is a genetic blood disorder with a deficiency in the Hemoglobin Beta Chain, requiring blood transfusion therapy. Multiple blood transfusions increase the risk of transmitting blood-borne infections. The aim of this study is to determine the frequency of hepatitis C virus (HCV) infection in Iranian individuals with β-thalassemia major. A total of 164 patients with β-thalassemia major were recruited for this study. HCV RNA testing was done on plasma and peripheral blood mononuclear cells (PBMCs) from the HCV seropositive samples (with reverse transcriptase-nested polymerase Chain reaction [PCR] method using primers from the 5'-untranslated region [UTR]), and all HCV RNA positive samples were genotyped by the restriction fragment length polymorphism assay. For confirmation of the HCV genotyping in PBMCs of occult HCV infection [OCI]-positive patients, the PCR products of two different regions of HCV (5'-UTR and nonstructural protein 5B [NS5B]) were sequenced. Of 164 patients, 29.3% were positive for anti-HCV antibodies, and HCV RNA was detected in the plasma specimens of 13.4% patients and in the PBMC samples of 15.2% participants. The genomic HCV-RNA was detected in PBMC samples in 3 (6.3%) of the total 48 individuals who were HCV seropositive, and plasma HCV-RNA negative (occult HCV infection). The subtypes of HCV in the plasma and PBMC samples of three participants were not identical. This study shows that among this group of Iranian patients with β-thalassemia major, 13.4% had active HCV infection and 6.3% had occult HCV infection as evidenced by HCV RNA detected in PBMC specimens. Therefore, the design of a prospective study that focuses on the diagnosis of OCI can be very valuable and provide more information.
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Prevalence of occult hepatitis C virus infection in Iranian patients with Beta thalassemia major
Archives of Virology, 2016Co-Authors: Mohammad-navid Bastani, Farah Bokharaei-salim, Hossein Keyvani, Maryam Esghaei, Seyed Hamidreza Monavari, Mojtaba Ebrahimi, Saba Garshasebi, Shahin FakhimAbstract:Occult hepatitis C virus infection (OCI) is a new pathological form of chronic hepatitis virus (HCV) infection characterized by the presence of HCV RNA in liver biopsy and/or peripheral blood mononuclear cell (PBMC) specimens and the absence of HCV RNA and anti-HCV antibodies (Abs) in plasma samples. β-thalassemia major is a hereditary recessive blood disease with deficiency in the Hemoglobin Beta Chain. Thalassemic patients need blood transfusion therapy; repeated blood transfusion increases the risk of viral blood-borne infection. The aim of this study was to determine the prevalence of OCI in Iranian patients with β-thalassemia major. From February 2015 to November 2015, a total of 147 Iranian patients with β-thalassemia major were enrolled in this cross-sectional study. After extraction of viral RNA from the plasma and PBMC samples, HCV genomic RNA in the specimens was amplified by RT-nested PCR using primers from the 5′-UTR. The HCV genotypes of the positive specimens were tested using the RFLP assay. To confirm the HCV genotypes, the 5′-UTR fragment was amplified and cloned into the pJET1.2/blunt cloning vector and then sequenced. Out of 147 patients, 106 (72.1 %) were negative for anti-HCV Abs and HCV RNA. HCV RNA was found in PBMC specimens of six (5.7 %) patients, from a total of 106 patients with undetectable plasma HCV RNA and anti-HCV Abs. Therefore, six out of 106 patients had OCI. HCV genotyping revealed that three patients were infected with HCV subtype 1b, two patients were infected with HCV subtype 3a, and one patient was infected with HCV subtype 1a. These results revealed that Iranian patients with Beta-thalassemia major might have OCI. Therefore, it seems that the design of a study to identify this infection in patients with β-thalassemia major would provide valuable information.
Farah Bokharaei-salim - One of the best experts on this subject based on the ideXlab platform.
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Detection of HCV genome in peripheral blood mononuclear cells of Iranian seropositive and HCV RNA negative in plasma of patients with Beta‐thalassemia major: Occult HCV infection
Journal of Medical Virology, 2018Co-Authors: Roya Kahyesh‐esfandiary, Mohammad-navid Bastani, Maryam Esghaei, Zohreh-azita Sadigh, Tahereh Donyavi, Alireza Najafi, Atousa Fakhim, Farah Bokharaei-salimAbstract:: Beta (β) thalassemia major is a genetic blood disorder with a deficiency in the Hemoglobin Beta Chain, requiring blood transfusion therapy. Multiple blood transfusions increase the risk of transmitting blood-borne infections. The aim of this study is to determine the frequency of hepatitis C virus (HCV) infection in Iranian individuals with β-thalassemia major. A total of 164 patients with β-thalassemia major were recruited for this study. HCV RNA testing was done on plasma and peripheral blood mononuclear cells (PBMCs) from the HCV seropositive samples (with reverse transcriptase-nested polymerase Chain reaction [PCR] method using primers from the 5'-untranslated region [UTR]), and all HCV RNA positive samples were genotyped by the restriction fragment length polymorphism assay. For confirmation of the HCV genotyping in PBMCs of occult HCV infection [OCI]-positive patients, the PCR products of two different regions of HCV (5'-UTR and nonstructural protein 5B [NS5B]) were sequenced. Of 164 patients, 29.3% were positive for anti-HCV antibodies, and HCV RNA was detected in the plasma specimens of 13.4% patients and in the PBMC samples of 15.2% participants. The genomic HCV-RNA was detected in PBMC samples in 3 (6.3%) of the total 48 individuals who were HCV seropositive, and plasma HCV-RNA negative (occult HCV infection). The subtypes of HCV in the plasma and PBMC samples of three participants were not identical. This study shows that among this group of Iranian patients with β-thalassemia major, 13.4% had active HCV infection and 6.3% had occult HCV infection as evidenced by HCV RNA detected in PBMC specimens. Therefore, the design of a prospective study that focuses on the diagnosis of OCI can be very valuable and provide more information.
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Prevalence of occult hepatitis C virus infection in Iranian patients with Beta thalassemia major
Archives of Virology, 2016Co-Authors: Mohammad-navid Bastani, Farah Bokharaei-salim, Hossein Keyvani, Maryam Esghaei, Seyed Hamidreza Monavari, Mojtaba Ebrahimi, Saba Garshasebi, Shahin FakhimAbstract:Occult hepatitis C virus infection (OCI) is a new pathological form of chronic hepatitis virus (HCV) infection characterized by the presence of HCV RNA in liver biopsy and/or peripheral blood mononuclear cell (PBMC) specimens and the absence of HCV RNA and anti-HCV antibodies (Abs) in plasma samples. β-thalassemia major is a hereditary recessive blood disease with deficiency in the Hemoglobin Beta Chain. Thalassemic patients need blood transfusion therapy; repeated blood transfusion increases the risk of viral blood-borne infection. The aim of this study was to determine the prevalence of OCI in Iranian patients with β-thalassemia major. From February 2015 to November 2015, a total of 147 Iranian patients with β-thalassemia major were enrolled in this cross-sectional study. After extraction of viral RNA from the plasma and PBMC samples, HCV genomic RNA in the specimens was amplified by RT-nested PCR using primers from the 5′-UTR. The HCV genotypes of the positive specimens were tested using the RFLP assay. To confirm the HCV genotypes, the 5′-UTR fragment was amplified and cloned into the pJET1.2/blunt cloning vector and then sequenced. Out of 147 patients, 106 (72.1 %) were negative for anti-HCV Abs and HCV RNA. HCV RNA was found in PBMC specimens of six (5.7 %) patients, from a total of 106 patients with undetectable plasma HCV RNA and anti-HCV Abs. Therefore, six out of 106 patients had OCI. HCV genotyping revealed that three patients were infected with HCV subtype 1b, two patients were infected with HCV subtype 3a, and one patient was infected with HCV subtype 1a. These results revealed that Iranian patients with Beta-thalassemia major might have OCI. Therefore, it seems that the design of a study to identify this infection in patients with β-thalassemia major would provide valuable information.
Grady R Blacken - One of the best experts on this subject based on the ideXlab platform.
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cysteine 93 of Hemoglobin Beta Chain is the major target of oxidation during red blood cell storage
Blood, 2009Co-Authors: Grady R Blacken, Yi Wang, Jose A Lopez, Xiaoyun FuAbstract:Abstract 4040 Poster Board III-976 Red blood cells (RBC) stored for prolonged time periods under blood banking conditions are known to accumulate irreversible damage that ultimately affects their viability and function. Among the consequences of this RBC storage lesion are enhanced hemolysis and oxidative stress after transfusion. Stored RBCs accumulate reactive oxygen species (ROS) and surface-associated hemichrome, a partially denatured form of oxidized Hemoglobin. In this work, we examined whether the ROS created during RBC storage lead to characteristic oxidative modifications to Hemoglobin (Hb) and RBC membrane proteins. To characterize Hb modifications leading to hemichrome formation, we oxidized human Hemoglobin A with varied concentrations of hydrogen peroxide (H2O2), an oxidant relevant to RBC storage. The reaction was quenched with excess methionine and the protein digested with trypsin. The resulting peptides were analyzed by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). Methionine and cysteine residues are the major targets of oxidation. Oxidation of methionine to methionine sulfoxide and cysteine to cysteine sulfonic/sulfinic acids is accompanied by a mass shift related to the covalent modifications of each residue, which are readily detected by LC-ESI-MS/MS. We found that HBβ-Cys-93 was oxidized to a maximum of approximately 70% after treatment with 200 αM H2O2. This cysteine occurs adjacent to the FeII-coordinating His-92 and is thus exposed to the heme-FeII center. In contrast, HBβ-Cys-112 and HBα-Cys-104, which are buried and located away from the heme-FeII center, were oxidized to only 2% and 0%, respectively. The enhanced oxidation of the heme-FeII proximal HBβ-Cys-93 suggests that ROS are generated through a FeII-dependent mechanism such as Fenton9s reaction. Oxidation of each of the three Hb methionines reached 20% upon treatment with 200 μM H2O2. Among these Met residues, HBα-Met-32 is located near the heme-FeII, center, while both Hbα-Met-76 and HBβ-Met-55 are near the protein/solvent interface. Thus, Cys and Met oxidations in Hb appear to be dependent on proximity to either the heme-FeII center or the protein/solvent interface. To test whether these Hb residues are also sensitive to oxidation during storage we acquired 3 RBC units stored for 3 days and 3 RBC units stored for 45 days, from the Puget Sound Blood Center. The cytosolic Hb was extracted by hypotonic lysis and digested with trypsin prior to LC-ESI-MS/MS analysis. We observed that oxidation of HBβ-Cys-93 was dramatically increased from 10% on day 3 to 29% on day 45 (p Our observations suggest that HBβ-Cys-93 oxidation is a specific and sensitive marker for oxidative stress during storage. Moreover, we have correlated these progressive oxidations with increases in microvesiculation and hemolysis, storage-time-dependent changes that have been well documented. Future studies will evaluate the storage-time-dependence in other oxidative and post-translational modifications to RBC membrane proteins and correlate these findings with functional consequences such as microvesiculation and hemolysis. Disclosures: No relevant conflicts of interest to declare.