Hemoglobin A Research Articles

Hemoglobin S Exhibits Distinct MRI Oximetry Calibration in Vitro

Cerebral oxygen extraction fraction (OEF) is a powerful biomarker that could be used to stratify cerebrovascular morbidity in patients with sickle cell disease (SCD). Recently, several MRI intravascular oximetry techniques have demonstrated early feasibility in non-invasively quantitating OEF. Critical to this technique is the use of empirically derived calibrations that convert the measured magnetic relaxation property, T2, into oxygen saturation. Previous work demonstrated a strong hematocrit and saturation dependence on T2 and our prior work extended early results to hematocrit ranges common in patients with chronic anemia1. Despite improvements in calibration models, it remains an unanswered question whether the unique hemorheologic properties of hemoglobin S (HbS) containing red cells will give rise to fundamentally distinct magnetic properties compared to healthy, hemoglobin A (HbA) cells.Methods: All studies were performed on at CHLA under an IRB protocol with consent/assent. The blood of 11 subjects with sickle cell disease were studied (6 Male, 5 Female, aged 25.4 ± 14.5 years). Six had HbSS, three had HbSC, and two had HbSB0). Three of the subjects were on chronic transfusion therapy (2HbSS, 1 HbSB0). Two tablespoons of blood was drawn for the antecubital vein and stored at 4°C until analysis. For analysis, blood was placed in a custom built imaging apparatus and heated to 37° C. Oxygen level was measured with a hemoximeter and T2 was measured within a 3T Philips scanner. Following the T2 measurement blood was removed from the imaging apparatus and desaturated in a temperature controlled chamber using a membrane oxygenator and 5% CO2 and 95% N2 gas mixture. MRI T2 measurements and deoxygenation were repeated until a blood saturation level of ~30% was reached. T2 was measured with a phase cycled, CPMG sequence with 0, 4, 8 16 inversions pulse and a tau of 10ms. Monoexponetial fitting was used to derive T2.Results: Our previous work using a similar system and HbA blood demonstrated a highly reproducible relationship linking T2 to hematocrit and oxygen saturation (Y) as follows:R2= 1/T2 = A1*HCT*(1-Y)2 + A2*(1-Y)2 + A3*HCT + A4where the coefficients A1, A2, A3, and A4 were fit to data from a broad range of hematocrit and oxygen saturation values. In blood from sickle cell patients, we found that the A1 and A3 terms were zero. Thus the calibration curve was essentially independent of hematocrit. Figure 1 shows the tight relationship between hematocrit and 1/T2 for HbA could not be reproduced in HbS blood. In Figure 2, 1/T2 maintained a tight relationship (R2=.981) with (1-Y)2. The slope of 1/T2 and (1-Y)2was higher in HbS blood compared to HbA. There was also a positive relationship between HbS% and the residual of (1-Y)2 and R2 however this is was a weak effect (R2=0.057).Discussion: We found that the T2 of HbS containing red cells is distinct from the healthy HbA containing cells. This work has clinical implications for intravascular MRI oximetry performed in patients with sickle cell disease2 in that neglecting the magnetic differences between HbA and HbS may result in a 9.5%± 2.8% average bias in absolute saturation at a HCT of 32% . Interestingly, we were unable find a difference across sickle phenotypes and only small differences in transfused vs nontransfused patients. We suspect that irreversibly sickled cells, even few in number, will greatly influence the local magnetic field and shorten the T2 of sickle blood. It remains to be shown whether the in vitro conditions of this experiment are applicable to in vivo condition more broadly. In-vivo cross-validation studies are ongoing.1). Bush et al. MRM 20162). Jordan LC et al. Brain 2016Jordan LC, Gindville MC, Scott AO, et al. Non-invasive imaging of oxygen extraction fraction in adults with sickle cell anaemia. Brain2016;139(Pt 3):738-5 [Display omitted] [Display omitted] DisclosuresWood:World Care Clinical: Consultancy; Celgene: Consultancy; World Care Clinical: Consultancy; Vifor: Consultancy; Vifor: Consultancy; Ionis Pharmaceuticals: Consultancy; Ionis Pharmaceuticals: Consultancy; Celgene: Consultancy; AMAG: Consultancy; AMAG: Consultancy; Apopharma: Consultancy; Apopharma: Consultancy; Biomed Informatics: Consultancy; Biomed Informatics: Consultancy.

A Novel Recombinant Eklf-GATA1 Fusion Protein Reduces Sickling of Erythrocytes Cultured from CD34+ Cells with Sickle Cell Disease

Current gene therapy approaches for treatment of hemoglobinopathies involve viral transduction of hematopoietic stem cells with antisickling globin genes. Hemoglobin A2 (HA2, α2δ2), expressed at a low level due to the lack of Eklf binding motif in its promoter region, is fully functional and could be a valid anti-sickling agent in sickle cell disease, as well as a substitute of hemoglobin A in β-thalassemia. We had previously demonstrated that two Eklf-GATA1 fusion proteins could significantly activate δ-globin expression in CD34+ cells from healthy and sickle trait donor’s blood. Here we report the effects of Eklf-GATA1 on hemoglobin expression and phenotypic correction using erythrocytes cultured from CD34+ cells with sickle cell disease. We found that enforced expression of Eklf-GATA1 fusion protein enhanced globin gene expression in the erythrocytesas compared with vector control. The long-form Eklf-GATA1 up-regulated β-globin gene expression 2.0-fold, δ-globin gene expression 4.3-fold, and γ-globin gene expression 2.6-fold. The medium-form EKLF-GATA1 up-regulated δ-globin gene expression 2.3-fold and γ-globin 1.3-fold, but had no significant effect on β-globin gene expression. HPLC revealed a percentage of HA2+HbF was increased from 8.1 % in vector-transduced cells to 19.7% in medium-form Eklf-GATA-transduced-cells (p<0.01) and 14.4% in long-form Eklf-GATA-transduced-cells (p<0.01). Upon deoxygenation, the percentage of sickling erythrocyte was lower to 79.8% in medium-form Eklf-GATA-transduced cells as compared with 89.8% in vector-transduced-cells (p<0.05). Flow cytometry analyses of CD71/GPA and thiazole orange staining indicated that erythroid cell differentiation and enucleation were not affected by Eklf-GATA1. Our results shown that long form Eklf-GATA1 fusion protein has major effects on d- and g-globin induction than β-globin; the medium form Eklf-GATA1 elevated δ- and γ-globin expression without an effect on β-globin expression. Our results indicate that these fusion constructs could be a valuable genetic therapeutic tool for hemoglobinopathies, and warrant further preclinical study and evaluation. DisclosuresNo relevant conflicts of interest to declare.

Value of Analyzing Hemoglobin A2 by ROC Curve for Screening Thalassemia

To investigate the value of hemoglobin A2(HbA2) for screening thalassemia. A total of 2 000 adults' peripheral blood samples from Guangdong Women and Children Hospital from June 2013 to January 2014 were collected. The hemoglobin A2 (HbA2) level was analyzed by the full automatic capillary electrophoresis technique, and the genotypes of thalassemia were detected. The optimal cutoff values of HbA2 for screening silent α-thalassemia, α-thalassemia trait, intermedia α-thalassemia and β-thalassemia trait were 2.85%, 2.65%, 2.25% and 3.45%, respectively; the areas under receiver operator characteristic (ROC) curve were 0.709, 0.839, 0.979 and 0.997 respectively; the sensitivities were 0.481, 0.721, 0.953 and 0.994, and the specificities were 0.846, 0.837, 0.929 and 0.969 respectively. The optimal cutoff values of HbA2 for screening different type of thalassemia based on our laboratory data are established by using ROC curve. According to the area under ROC curve, a satisfactory accuracy for screening intermedia α-thalassemia and β-thalassemia trait can be achieved by detecting hemoglobin A2 level.

Coinheritance of B-Thalassemia and Sickle Cell Anaemia in Southwestern Nigeria.

Genes for haemoglobin S are found in high frequencies in Nigeria. However, there is little information on beta thalassemia in sickle cell anaemia in this population. The clinical presentation of HbS- β thalassemia is enormously variable, ranging from an asymptomatic state to a severe disorder similar to homozygous sickle cell disease. Haemoglobin A2 and HbF were determined in sickle cell anaemia patients attending LAUTECH Teaching Hospital, Osogbo, by elution after electrophoresis and alkaline denaturation methods respectively. Haematological parameters were estimated using Sysmex KX-21N and percentage target cells using Leishman's staining technique. Exactly 6% f the SCA patients were found to have elevated HbA2 (>3.3%) and HbF (>1.3%). These patients also had normal erythrocyte indices, increased platelet count, a significantly higher HCT and an increased % target cell. These findings confirm that the frequency of beta thalassaemia in sickle cell patients in Nigeria is higher than previously thought. It is therefore important to consider the possibility of this variant in patients with sickle cell anaemia since their course may differ from that of patients with homozygous sickle cell anaemia.

Motivational Interviewing and Compliance with Carriers Screening for Beta-Thalassemia Trait in Zahedan Premarital Counseling Center, Iran

Background: Screening and early genetic counseling programs for beta-thalassemia (BT) are of paramount importance during the pre-pregnancy period in high-risk individuals. Objectives: The current study aimed to evaluate the efficacy of motivational interviewing on couples` compliance with carriers screening for BT. Methods: The study was performed on 80 couples with suspected blood indexes for thalassemia trait (mean corpuscular volume (MCV) < 80 and/or mean corpuscular hemoglobin (MCH) < 27 and hemoglobin (Hb) A2 ≤ 3.5), referred to Zahedan premarital counseling center (PCC), Iran, from April 2015 to January 2016. The participants were randomly divided into motivational interviewing (MI) and routine care (control) groups; compliance was considered as number of couples referring to the center after 30 days post-intervention for re-evaluation of blood indexes, and in the second phase, if needed, referring to Zahedan prenatal diagnosis (PND) center for genetic testing, within five months. Results: In the first phase, noncompliance rates were 9.86% and 26.03% for the motivational interviewing (MI) and control groups, respectively. Preventive fraction (PF) indicated a 62% reduction in noncompliance after one month. In the second phase, five months after MI, noncompliance rates were 79.17% and 94.74% in the MI and control groups, respectively (PF=0.17). Conclusions: The MI group showed better compliance with short-term BT screening program, evidenced by higher rates of referral to the PCC.

A Clinico-Haematological study of hemoglobin E disease and trait

Introduction: HbE (Haemoglobin E) is one of the most important and common haemoglobinopathy. Its definitive diagnosis can be made on capillary electrophoresis. Our study aimed to analyze the clinico-haematological profile of patients having haemoglobin E disease and trait, including findings on capillary electrophoresis and iron profile. Materials and Methods: The samples were taken from patients who were referred to the haematology section of Department of Pathology, Silchar Medical College from January 2013 to December 2013. These patients were suspected of having haemoglobinopathy based on Peripheral Blood Film and Complete Blood Count. Study of complete haematological, eletrophoretic (by Capillary electrophoresis) and iron profile of the patients was done. Result: In our study, abnormal haemoglobins were detected in 61 out of the 100 cases examined, out of which HbE was detected in 45 cases. These patients presented with an asymptomatic to symptomatic phenotype, a decrease in mean corpuscular volume , microcytosis and target cells , a normal iron profile and increased HbE as well as HbA2 (Haemoglobin A2) levels on Capillary electrophoresis. Conclusion: Haemoglobin E constitutes an important haemoglobinopathy in lower Assam. An important finding was raised HbA2 (usually 6%) along with raised HbF levels. Therefore a proper diagnosis is essential so that preventive measures could be undertaken to reduce the burden of this haemoglobinopathy.

GBT440 Inhibits Sickling of Sickle Cell Trait Blood Under In Vitro Conditions Mimicking Strenuous Exercise.

In sickle cell trait (SCT), hemoglobin A (HbA) and S (HbS) are co-expressed in each red blood cell (RBC). While homozygous expression of HbS (HbSS) leads to polymerization and sickling of RBCs resulting in sickle cell disease (SCD) characterized by hemolytic anemia, painful vaso-occlusive episodes and shortened life-span, SCT is considered a benign condition usually with minor or no complications related to sickling. However, physical activities that cause increased tissue oxygen demand, dehydration and/or metabolic acidosis leads to increased HbS polymerization and life-threatening complications including death. We report that GBT440, an agent being developed for the treatment of SCD, increases the affinity of oxygen for Hb and inhibits in vitro polymerization of a mixture of HbS and HbA that simulates SCT blood. Moreover, GBT440 prevents sickling of SCT blood under in vitro conditions mimicking strenuous exercise with hypoxia, dehydration and acidosis. Together, our results indicate that GBT440 may have the potential to protect SCT individuals from sickling-related complications during conditions that favor HbS polymerization.

PS 02-17 IS GLYCATED HEMOGLOBIN LEVEL AND SUBCLINICAL ATHEROSCLEROSIS RELATED IN NON-DIABETIC INDIVIDUALS?

Objective: To analyze the relationship between glycated hemoglobin A1 (HbA1c) levels and subclinical atherosclerosis assessed by carotid intima-media thickness (IMT), presence of carotid plaque (CP) and pulse wave velocity (PWV) in patients without diabetes. Design and Method: From January 2011 through December 2012, carotid IMT and CP presence were evaluated in 214 non-diabetes patients (118 male, 96 female) with measurement of HbA1c, ankle-brachial index (ABI), brachial/femoral and heart to femoral PWV. HbA1c level was categorized into 3 groups (< 5.5%, 5.5% to 5.9%, and 6.0% to 6.4%). Results: Baseline characteristics were similar between three groups except age. There were no significant linear trends between groups either in PWV and carotid IMT measurement; however, the presence of CP showed significant linear trend (P for trend = 0.004). Odd ratios (ORs) of univariate model for presence of CP was 2.36 and 3.6 in the middle (5.5 ≤ HbA1c < 6.0) and highest HbA1c (6.0 ≤ HbA1c < 6.5) group compared with the lowest group (HbA1c < 5.5%) (p = 0.018 and p = 0.009, respectively). Sub-analysis of 115 non-diabetic patients (57 male, 58 female) with hypertension showed poor agreement in linear increase of carotid IMT, PWV measurements and plaque presence according to the elevation of HbA1c level which the result might have been influenced by other factors. Conclusions: Carotid IMT and PWV in non-diabetic individuals had poor correlation with HbA1c level; however, there was a significant linear relation between three groups in presence of CP.

A 5-year prospective study of type 2 diabetes patients in Shanghai Xinjing Community 2.The risk factors of diabetic retinopathy progression in type 2 diabetic residents with controlled blood glucose

Background Some diabetic patients with well controlled blood glucose still had diabetic retinopathy(DR). The risk factor of DR progression in Mongoloid was not clear. Objective This study was to assess the 5-year incidence and risk factors of DR progression in type 2 diabetic patients with controlled blood glucose. Methods A prospective study was performed under the informed consent of the patients.453 patients with glycosylated hemoglobin A1c (HbA1c)<7.0% in Shanghai xinjing Community from 2007 to 2012 were included in this study.The baseline survey started in 2007 and the final survey ended in 2012.The comprehensive examinations were carried out annually during the follow-up which including general information collection, systemic physical examination, laboratory examination and ophthalmological test.Forward Logistic regression and Cox regression were performed to analysis potential risk factors of DR progression.Kaplan-Meier survival analysis was performed to compare DR progress probability of patients with different HbA1c level.This study was approved by Shanghai First People's Hospital Ethics Committee Results Among the 453 type 2 diabetic patients, 146 developed or progressed DR during the follow-up.The 5-year DR progression rate was 32.23%.Logistic regression showed that baseline HbA1c level was the only independent risk factor of DR progression [P<0.01, odds ratio(OR)=2.84, 95% confidence interval (CI): 2.11-3.82]. Cox regression results showed that the incidence of DR progression in the baseline HbA1c≥5.2% patients was 1.97 times higher than that in the baseline HbA1c<5.2% patients [P<0.01, relative risk(RR)=1.97, 95%CI: 1.32-2.93]. Conclusions The progression rate of DR in type 2 diabetic patients with controlled blood glucose level is still high.In order to reduce DR progression in Chinese type 2 diabetic patients, the targeted HbA1c should be set to a lower level (under 5.2%) under the premise of absent severe side effects. Key words: Diabetes, type 2; Diabetic retinopathy; Hemoglobin A, glycosylated; Risk factor

Quantitative, Point-of-Care Immunoassay Platform to Guide and Monitor Sickle Cell Disease Therapy.

Sickle cell patients often require monthly transfusions with normal blood to treat the many complications of the disease. In this therapy, the clinician lowers the amount of hemoglobin S (HbS) containing red blood cells (RBCs) by transfusing normal blood units containing hemoglobin A (HbA). We have developed a point-of-care (POC) quantitative immunoassay for HbS to serve as a diagnostic aid for clinicians providing this life-saving treatment. The test consists of a small-footprint reader and cartridges that quantify the percentage of HbS in a small volume of patient blood. The test reports % HbS values in the range from 5 to 86% that highly correlate (slope 1.03, R(2) = 0.97) with currently used central laboratory HPLC systems. The test also shows a 1% limit of blank, 2% limit of detection, and 5% limit of quantitation. The test was also shown to encounter minimal effects from potential interferences. This cost-effective, POC HbS quantitative approach will allow for real-time transfusion monitoring in sickle cell treatment settings and therefore improve workflow and allow clinicians to quickly make informed therapeutic decisions.

Higher minor hemoglobin A2 levels in multiple sclerosis patients correlate with lesser disease severity.

ObjectiveTo define whether minor adult hemoglobin A2 (HbA2, α2δ2) exerts any protective activity in multiple sclerosis (MS).MethodsHbA2 levels were measured in 146 MS patients with high performance liquid chromatography and association with MS Severity Scores (MSSS) were determined. HbA2 associations with blood count parameters were also studied using blood counts evaluated on the same day of high performance liquid chromatography sampling. Routine biochemical parameters were also determined to rule out elusively influential factors, such as anemia and thyroid disorders.ResultsHbA2 levels negatively correlated with MSSS (Spearman correlation, R: −0.186, P=0.025). Exclusion of confounding factors with a generalized linear model revealed an even stronger negative correlation between HbA2 and MSSS (P<0.001). HbA2 positively correlated with red blood cells (RBCs) (R=0.350, P<0.001) and in turn, RBCs negatively correlated with MSSS (R=−0.180, P=0.031). Average HbA2 levels were highest among patients treated with interferon β1a.ConclusionRBC fragility is increased in MS, and recent data suggest that circulating free Hb contributes to neural injury in MS. HbA2 and its oxidative denaturation product hemichrome A2 enhance RBC membrane stability to a greater extent than do major HbA or hemichrome A. Reductions in ischemic cerebrovascular vascular events are reported in β-thalassemia carriers and HbA2 levels are considerably higher in this population. Episodic declines of cerebral blood flow were shown in bipolar disorder, and we have recently shown a protective role of HbA2 against postpartum episodes in females with bipolar disorder. HbA2’s erythroprotective functions may reduce free Hb and long-term neural injury in MS.

Q Sepharose micro-column chromatography: A simple screening method for identifying beta thalassemia traits and hemoglobin E carriers

ObjectivesFor beta thalassemia control program in pregnancy, mass screening of the carrier state by determination of the hemoglobin (Hb) A2 and Hb E proportions and mutation analysis is a preferred method for making prenatal diagnoses. Q Sepharose micro-column chromatography, developed for the determination of Hb A2 and Hb E for screening purposes, was compared with high performance liquid chromatography (HPLC) to ascertain its relative accuracy and reliability. Design and methodsResults using Q Sepharose micro-column chromatography in 350 blood specimens, including 50 samples genetically proven to be beta thalassemia heterozygotes, were compared to HPLC for validation. An additional study was conducted to test a clinical application on a large-scale survey for beta thalassemia in 1581 pregnant women and their spouses. ResultsThe mean (±SD) Hb A2 proportions in the normal and genetically proven beta thalassemia heterozygotes were 2.70±0.40% and 6.30±1.23%, respectively, as determined by Q-Sepharose micro-column chromatography, and 2.65±0.31% and 5.37±0.96%, respectively, as determined by HPLC. The mean Hb E proportions in the Hb E heterozygotes were 23.25±4.13% and 24.72±3.5% as determined by Q Sepharose micro-column chromatography and HPLC, respectively. In the large-scale survey for beta thalassemia, 23 at risk couples were detected. Seven affected fetuses were identified by prenatal diagnosis. ConclusionsQ Sepharose micro-column chromatography was found to be reliable, reproducible and well-suited for large-scale surveys. Additionally, by being reusable and convenient, this simple and economical chromatography method may be an alternative means to screen for beta thalassemia and Hb E carriers in the mass population.

The pros and cons of the fourth revision of thalassaemia screening programme in Iran

Objective To evaluate the repercussions of recent changes to the cut-offs used in the first screening step of the pre-marital screening programme for thalassaemia prevention in Iran. Methods The profiles of 984 subjects referred to a genetic laboratory, and the tests of 242 parents of children with thalassaemia major were assessed for red blood cell (RBC) indices, haemoglobin (Hb) A2 levels and results of Hb electrophoresis. Results Of 407 suspected thalassaemia minor (STM) cases, 18 proved positive for thalassaemia minor on molecular analysis (18/407, confidence interval 2.6-6.9%). If the revised screening cut-offs had been used to determine who would undergo molecular analysis, two of these cases would not have been identified. Only 4.4% of suspected cases with lower than normal RBC indices (mean corpuscular volume <80 fl and mean corpuscular Hb <27 pg) and HbA2 (<3.5%) were diagnosed with thalassaemia minor. Conclusion The thalassaemia major prevention programme is performed in two separate steps. One step involves the screening of subjects and identification of β-thalassaemia minor, suspected cases for thalassaemia minor (STM), and normal subject groups. The other step concerns the identification of thalassaemia minor in the STM group. Changing the cut-offs at the first screening step does not result in significant improvement from an economic view, and is associated with significant risk at the second screening step.

Reference intervals of HbA1c and fasting plasma glucose for pregnant women in Chongqing and the value of their combination in screening gestational diabetes mellitus

Objective To establish the reference intervals of hemoglobin A1c(HbA1c) and fasting plasma glucose(FPG) in the first and second trimester of pregnancy in Chongqing , and to evaluate the viability of the combination of HbA1c and FPG in screening gestational diabetes mellitus (GDM). Methods The study retrospectively selected the pregnant women seen at the Department of Obstetrics and Gynecology in Daping Hospital between September 2014 and August 2015. The results of FPG during 10-13 pregnant weeks and 75 g oral glucose tolerance test (OGTT) and HbA1c during 24-28 pregnant weeks were available.Totally 185 cases were assigned into GDM group, and 269 cases were assigned into normal group based on the American Diabetes Association (ADA) guidelines. Reference intervals of HbA1c and FPG in normal pregnant woman were developed. The difference of HbA1c, FPG and OGTT results between two groups was analyzed. T-student test, NcMemar test, signed rank sum test, ROC curve were used for statistical analysis. Results The reference intervals of HbA1c and FPG in first and second trimester were 4.58%-5.52%, 4.21-5.49 mmol/L and 4.03-5.08 mmol/L.The FPG level in first and second trimester and HbA1c level in GDM group vs normal group were(5.06±0.37) vs(4.85±0.32)mmol/L(t=6.569, P=0.000), 5.23(5.11, 5.4) vs 4.74(4.54, 4.91) mmol/L(z=-14.31, P=0.000)and 5.3(5.1, 5.4)% vs 5.2(5.0, 5.3)%(z=-5.79, P=0.000)respectively. The area under receiver operating characteristic curve (ROC) of HbA1c, and FPG in first and second trimester was 0.655, 0.659 and 0.890 respectively. When the cut-off value of HbA1c was 5.35%, the AUC of the combination of HbA1c and FPG in second trimester was 0.898, the sensitivity was 0.838, and the specificity was 0.859.The kappa coefficient for identifying GDM between OGTT and the combined method was 0.692(P=0.000). Conclusion HbA1c combined with FPG is of some value in screening GDM.(Chin J Lab Med, 2016, 39: 413-417) Key words: Diabetes, gestational; Hemoglobin A, glycosylated; Blood glucose; Reference values

Developing a reference system for the IFCC standardization of HbA2

The importance of hemoglobin A2 (HbA2) as an indicator of the presence of β-thalassemia was established many years ago. However, clinical application of recommended HbA2 cut off values is often hampered due to poor equivalence of HbA2 results among methods and laboratories. Thus, the IFCC standardization program for HbA2 was initiated in 2004 with the goal of achieving a complete reference system for this measurand. HbA2 standardization efforts are still in progress, including the development of a higher-order HbA2 reference measurement procedure and the preparation of a certified reference material in collaboration with the IRMM. Here, we review the past, present and future of HbA2 standardization and describe the current status of HbA2 testing.

Factors influencing glucose metabolism in young obese subjects with obstructive sleep apnea hypopnea syndrome

To explore the factors influencing glucose metabolism in young obese subjects with obstructive sleep apnea hypopnea syndrome (OSAHS). A total of 106 young obese subjects[18-44 years old, body mass index (BMI) ≥30 kg/m(2)]were enrolled and divided into two groups based on full-night polysomnography (PSG), OSAHS group[apnea hypopnea index (AHI) ≥5 events/h]and non-OSAHS group (AHI<5 events/h). Oral glucose tolerance-insulin releasing test (OGTT-IRT) was performed and serum glycosylated hemoglobin A1 (HbA1c) levels were measured after an overnight fast. Homeostasis model assessment-IR (HOMA-IR), Matsuda insulin sensitivity index (MI), homeostasis model assessment-β (HOMA-β), the early phase insulinogenic index (ΔI(30)/ΔG(30)), total area under the curve of insulin in 180 minutes (AUC-I180) and oral disposition index (DIo) were calculated to evaluate insulin resistance and pancreatic β cell function. Stepwise multiple linear regressions were conducted to determine the independent linear correlation of glucose measurements with PSG parameters. Prevalence of diabetes was higher in OSAHS than in non-OSAHS group (22.0% vs 4.3%, P=0.009). OGTT 0, 30, 60 min glucose and HbA1c levels were higher in OSAHS group than those in non-OASHS group (all P<0.05). DIo were lower in OSAHS group than those in non-OASHS group (P=0.024), HOMA-IR, MI, HOMA-β, ΔI(30)/ΔG(30), and AUC-I(180) were similar between two groups (all P>0.05). In stepwise multiple linear regressions, OGTT 0, 30 and 60 min glucose were positively correlated with oxygen desaturation index (ODI) (β=0.243, 0.273 and 0.371 respectively, all P<0.05). HOMA-β was negatively correlated with AHI (β=-0.243, P=0.011). DIo was negatively correlated with ODI (β=-0.234, P=0.031). OSAHS worsens glucose metabolism and compensatory pancreatic β-cell function in young obese subjects, which could probably be attributed to sleep apnea related oxygen desaturation during sleep.

Glycosylated Hemoglobin and Functional Outcome after Acute Ischemic Stroke

Diabetes mellitus (DM) is associated to an increased incidence of cerebral and myocardial infarction which could be reduced by long-term maintenance of optimal glycemic values. The aim of the study was to evaluate in diabetic patients with ischemic stroke the chronic glycemic status and its relationship with functional outcome. We retrospectively identified consecutive diabetic patients hospitalized for acute ischemic stroke. Clinical and biochemical characteristics at admission were assessed. The outcome measures were the attainment of the recommended glycosylated hemoglobin A1 (HbA1c) level and the 3-month functional status according to the modified Rankin Scale score. Among the 112 enrolled patients, 39 (34.8%) met the recommended goal of HbA1c less than 7%. Higher education level was predictive of good prestroke glycemic control (adjusted OR 1.32 per year [95% CI 1.15-1.51], P < .001). At the 3-month evaluation, 44 (39.3%) patients were classified as having a poor outcome. After categorization of HbA1c values into tertiles, a dose-response relationship with poor functional recovery was found (P = .001). The suboptimal prestroke glycemic status was an independent predictor of unfavorable outcome (adjusted OR 6.22 [95% CI 1.94-19.98] for HbA1c ≥7%, P = .002). The management of DM was suboptimal in nearly two thirds of diabetic subjects presenting with acute ischemic stroke. The glycemic control before stroke occurrence was an independent prognostic factor and HbA1c values above the recommended goals increased the risk of unfavorable 3-month outcome. The improvement of DM management may be an effective strategy to either decrease the burden of cerebrovascular disease or influence its clinical course.

The First Report of a 290-bp Deletion in β-Globin Gene in the South of Iran.

Background:β-thalassemia is one of the most widespread diseases in the world, including Iran. In this study, we reported, for the first time, a 290-bp β-globin gene deletion in the south of Iran.Methods:Four individuals from three unrelated families with Arabic ethnic background were studied in Khuzestan Province. Red blood cell indices and hemoglobin analysis were carried out according to the standard methods. Genomic DNA was obtained from peripheral blood cells by salting out procedures. β-globin gene amplification, multiplex ligation-dependent probe amplification (MLPA), and DNA sequencing were performed.Results:The PCR followed by sequencing and MLPA test of the β-globin gene confirmed the presence of a 290-bp deletion in the heterozygous form, along with -88C>A mutation. All the individuals had elevated hemoglobin A2 and normal fetal hemoglobin levels.Conclusions:This mutation causes β0-thalassemia and can be highly useful for prenatal diagnosis in compound heterozygous condition with different β-globin gene mutations.

Introduction of new formulas and evaluation of the previous red blood cell indices and formulas in the differentiation between beta thalassemia trait and iron deficiency anemia in the Makkah region

Background: Many formulas from red blood cell (RCB) indices are instructed to differentiate between iron deficiency anemia (IDA) and beta thalassemia trait. None had 100% Youden index.Aim of the work: To introduce two new formulas and evaluate them in the differentiation between IDA and beta thalassemia trait in adults Saudi (male and female; male; female) in the Makkah region. Furthermore, to evaluate the previous formulas in our population.Methods: A total of 249 participants, 91 with IDA, 123 with beta thalassemia trait, and 35 healthy persons. All subjected to complete blood count, measurement of iron profile, hemoglobin electrophoresis and hemoglobin A2 by column chromatography. The first new formula equal hemoglobin (Hb) + hematocrit (Hct) + RBC and second equals Hb + Hct + RBC-red cell distribution (RDW). The previous formula used is England and Fraser, Mentzer, Strivastava, Ehsani, Green and King, red cell distribution index, Ricerca, and Shine and LalResults: In both men and women, the England and Fraser was the best with a Youden's index of 70.4%, followed by Green and King 67.4%. In men, the England and Fraser and our new formula 1 had the highest Youden’ index 84.7% and 84.1%, respectively. In women, the England and Fraser and RDW index had the highest Youden’ index 74% and 69.2%, respectively.Conclusion: The England and Fraser and our new formula 1 are the best formulas in men. The England and Fraser and RDW index are the best formulas in women.

Application of mRNA Expression Analysis to Human Blood Identification in Degenerated Samples that were False-negative by Immunochromatography.

Forensic laboratories are often faced with cases in which methamphetamine hydrochloride-mixed blood is unable to be identified as human blood by immunochromatography against human hemoglobin A0. The application of mRNA expression analysis to samples that showed a false-negative with immunochromatography was investigated as an alternative approach that did not depend on the antigen-antibody reaction. Real-time PCR was used to examine the expression levels of blood markers such as glycophorin A, spectrin beta, and hemoglobin beta. Hemoglobin beta was the only marker that was specifically detected in blood, while glycophorin A was useful for determining human specificity. Hemoglobin beta showed good detection sensitivity and was detectable in 37-year-old blood stains. Hemoglobin beta was exclusively detectable in methamphetamine hydrochloride-mixed blood stains. Detergents and disinfectants did not significantly influence mRNA markers. The proposed mRNA expression analysis was suitable for human blood identification as an alternative method to immunochromatography.