Role of Glycerol Oxidation Pathways in the Reductive Acid Leaching Kinetics of Manganese Nodules Using Glycerol.

Manganese nodules from ocean bed are potential resources of Cu, Ni, and Co for which land-based deposits are scarce in India. The present work describes a novel approach of using glycerol, a nontoxic biomass-derived reductant, for the reductive acid leaching of manganese nodules. Parameters such as acid concentration, time, temperature, and pulp density were optimized for leaching. The optimal leaching conditions were found to be 10% (w/v) pulp density and 10% (v/v) H2SO4 at 80 °C with 1% (v/v) glycerol yielding >95% of Ni and >98% Cu, Co, and Mn extraction within an hour. Kinetic analysis of the data based on the initial rate method showed that the leaching process was chemical reaction-controlled with an apparent activation energy of 55.47 kJ/mol. Various oxidation intermediates of glycerol formed during leaching were identified using mass spectrometry and Raman spectroscopy, and a probable oxidation pathway of glycerol during the leaching process has been elucidated based on the analysis. Glycerol was oxidized to glyceraldehyde, glyceric acid, tartronic acid, dihydroxyacetone, hydroxy pyruvic acid, glyoxalic acid, oxalic acid, and finally converted to CO2 during leaching. The fast reaction kinetics, near-complete dissolution of manganese, and other associated metals in the nodule can be attributed to the participation of all intermediate products of glycerol oxidation in redox reactions with MnO2, enhancing the overall reduction leaching efficiency.

Process Flowsheet Development for Separation of Sm, Co, Cu, and Fe from Magnet Scrap.

A complete process flowsheet to recover metal values from Sm2Co17-type magnet scrap was investigated. The magnet scrap was leached in chloride medium at pulp density of 2% (w/v) under the optimum conditions of 15% (v/v) HCl and 5% (v/v) H2O2 at 70 °C for 3 h, which yielded 98.5% Sm and 99% Co extractions. The full factorial Design of Experiment technique was adopted for the optimization of leaching conditions. Sm was selectively separated from the leach liquor as precipitated double salt using Na2SO4. The precipitated double sulfate was later converted to Sm-oxalate, which was subsequently calcined to produce pure Sm2O3. Following Sm separation, Fe was removed through precipitation by raising the pH to 3.0. For Cu and Co recovery, solvent extraction techniques using LIX 84I and Na-CYANEX 272, respectively, were followed. The McCabe-Thiele diagrams for extraction as well as stripping were presented for both Cu and Co.

Efficacy of Dichlorophenolindophenol (DCIP) as Screening Test for Hb E: Revisited.

Hb E-beta thalassemia is a major public health problem in West Bengal, India and is the predominant symptom producing thalassemia in this part of the country. To search for an easy, reliable and cost effective screening method for HbE that can be used at the community level where more sophisticated methods are not readily available. And the DCIP test was performed for the purpose. Blood samples of 425 asymptomatic family members from 80 diagnosed cases of HbE beta Thalassemia patients were tested for Hb, RBC indices, DCIP test, HPLC, and in discordant cases confirmed by DNA mutation analysis. The present study shows DCIP screening test to have a sensitivity, specificity, positive predictive value and negative predictive value of 96.39%, 97.43%, 96.39% and 97.43% respectively. It also shows a false positive rate and false negative rate in 2.56% and 4.6% cases respectively. The advantage with DCIP over HPLC is that it can be easily performed at the community level by a person with minimum technical skill, few samples (even a single sample) can be tested at time, at a low cost.

Molecular interactions of MnO2@RGO (manganese dioxide-reduced graphene oxide) nanocomposites with bovine serum albumin.

Graphene based materials have attracted global attention due to their excellent properties. GO-metal oxide nanocomposites have been conjugated with biomolecules for the development of novel materials and potentially used as biomarkers. Herein, a detailed study on the interaction of Bovine serum albumin (BSA) with MnO2@RGO (manganese dioxide-reduced graphene oxide) nanocomposites (NC) has been carried out. MnO2@RGO nanocomposites were prepared through a template/surfactant free hydrothermal route at 180 °C for 12 h by varying the graphene oxide (GO) concentration. Different biophysical experiments have been carried out to evaluate molecular interactions between BSA and NCs. Intrinsic fluorescence has been used to quantify the quenching efficiency of NCs and the binding association of BSA-NC complexes. NCs effectively quenched the intrinsic fluorescence of BSA via static and dynamic mechanism. Further, the results indicate that the molecular interactions of NC with BSA are dependent on the GO percentage in NC. Circular dichroism results demonstrate nominal changes in the secondary structure of BSA in presence of NCs. Also, the esterase-like activity of BSA was marginally affected after adsorption upon NCs. In addition, the FESEM micrographs reveal that the protein-NC complexes consist of nanorod and sheet-like morphologies are forming aggregates of different sizes. We hope that this study will provide a basis for the design of novel graphene based and other related nanomaterials for several biological applications.Communicated by Ramaswamy H. Sarma.

Does Profile of Hemoglobin Eß-thalassemia Patients Change After Splenectomy? Experience of a Tertiary Thalassemia Care Centre in Eastern India.

Hemoglobin Eß-thalassemia is by far the commonest form of thalassemia intermedia. Its phenotype ranges from mild anemia to severe transfusion-dependency necessitating splenectomy in many patients. The present study aimed to systematically analyze both clinical as well as laboratory parameters in profile of Eß-thalassemia patients after splenectomy in terms of transfusion requirement, infections and other complications. Retrospective study conducted over a period of 3 years included 72 cases of splenectomized Eß-thalassaemia patients, considering decrease in transfusion requirements, new complications, antibiotic, anti-malarial prophylaxis and iron chelation therapy. Out of 1380 registered Eß-thalassemia patients, 618 (44.78 %) were regularly transfused and 72(5.22 %) underwent splenectomy. Mean age of diagnosis was 10.3 years. Nineteen patients (26.4 %) underwent splenectomy between 5 and 10 years, 38 cases (52.7 %) between 10 and 20 years. The leading cause (51.39 %) for splenectomy was mechanical discomfort. Mean steady state hemoglobin raised from pre-splenectomy level of 5.43-6.8 gm/dl after splenectomy. Mean transfusion requirement reduced from 18.1 to 7.8 units/year. Mean serum ferritin level increased from 907.58 to 1,091.6 ng/ml. Post-splenectomy; 21 (29.17 %) patients developed facial deformities, 17 (23.6 %) delayed pubertal growth, 11 (15.28 %) venous thromboembolism, five (6.94 %) pulmonary hypertension and four (5.5 %) had extramedullary hematopoiesis. Five (6.96 %) patients had documented bacterial infections and two (2.78 %) suffered from malaria. Forty eight patients (66.67 %) started with iron chelation therapy; but majority (52.7 %) stopped. Major advantage of splenectomy is reduced transfusion requirement, though it cannot prevent skeletal abnormalities and delayed pubertal growth. In resource constraint countries like India, routine anti-malarial and antibacterial prophylaxis is not desirable; iron chelation therapy should be encouraged and ensured.

Effectiveness of Prenatal Screening for Hemoglobinopathies in a Developing Country.

The thalassemias are among the most common monogenic diseases worldwide, a national health burden in India. There are estimated 7500-12,000 babies born with ß-thalassemia major (ß-TM) every year in this country. Couples who are at-risk of having children with hemoglobin (Hb) disorders desired to have the option of avoiding the birth of an affected child by prenatal diagnosis (PND). Thus, the prenatal women are a highly important target group for carrier screening and preventing the birth of thalassemic children in the country. The present study was conducted among 20,883 pregnant women, irrespective of gravida and duration of pregnancy, from the prenatal clinic of Nilratan Sarkar (NRS) Medical College & Hospital, Kolkata, West Bengal, India, from February 2009 to November 2012. Thalassemia carrier status was assessed by high performance liquid chromatography (HPLC) along with red blood cell (RBC) indices. Husbands of all thalassemia carrier women were advised and persuaded to undergo screening for hemoglobinopathies. The couples were counseled to undergo PND if both of them were detected to be thalassemia carriers. The data were statistically analyzed to evaluate the efficacy of this procedure.

B cell suppression in newborn following treatment of pregnant diffuse large B-cell lymphoma patient with rituximab containing regimen.

Non-Hodgkin lymphoma associated with pregnancy is rare. Rituximab based chemotherapy is now considered the standard of care and considered safe for the treatment of diffuse large B-cell lymphoma (DLBCL) during pregnancy but little is known about its safety profile on the fetus. A 32 y primigravida was diagnosed as DLBCL at 20 wk of gestation. She received rituximab containing chemotherapy with successful pregnancy outcome. Though the baby was absolutely healthy, B-cell was totally absent in the cord blood.

Veno-occlusive disease following high dose melphalan.

Hepatic veno-occlusive disease (VOD) is one of the complications following bone marrow transplantation. This complication is uncommon after HDT for autologous SCT (ASCT) in patients with multiple myeloma (MM). Here we report on a 54 years male with MM developed VOD on day 16 of transplant. The Patient was died due to multi-organ failure. The present case suggests that after HDT for ASCT in patients with MM can complicated with VOD.

Prevalance of iron deficiency in thalassemia minor: a study from tertiary hospital.

Conflicting data are available about iron metabolism in thalassemia minors. As iron deficiency prevails largely in India, a study of 150 people was conducted to assess the iron level of ß thalassemia minor. The study population comprises of 59 males and 91 female who either attended outdoor services and with diagnosed thalassemia minor by hemoglobin high performance liquid chromatography or were the parents (diagnosed thalassemia minor) of ß Thalassemia patients visiting daycare services for transfusion. 29.67% females and 3.38% males are found to be iron deficient. Thus we can conclude that iron deficiency is one of the common co-existing conditions in ß thalassemia minors.

Prevalence of hemoglobinopathies in rural Bengal, India.

India is in the thalassemia belt of the world. Both α- and ß-thalassemia (α- and ß-thal) are found in West Bengal, a state in the eastern part of India. There was no systematic large published study to investigate the prevalence rates of different hemoglobinopathies in West Bengal. This study was conducted in school and college students, newly married couples and pregnant women after proper counseling in the rural areas of five districts of West Bengal state in eastern India. Thalassemia testing was done using high performance liquid chromatography (HPLC). A total of 35,413 individuals were screened for hemoglobinopathies. ß-Thalassemia trait was found in 10.38%, Hb E [ß26(B8)Glu→Lys] trait in 4.30%, sickle cell trait in 1.12%, borderline Hb A(2) value 0.73%, low Hb A(2) 0.68% and Hb D trait 0.37%. This is the first study that addresses the prevalence of different hemoglobinopathies in rural areas of West Bengal. The prevalence of ß-thal trait is higher in West Bengal than other parts of India. This data is likely to be helpful in planning screening programs in rural areas of West Bengal, India.