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1.
Transfusion ; 59(7): 2248-2254, 2019 07.
Article in English | MEDLINE | ID: mdl-31183877

ABSTRACT

BACKGROUND: CD47 is a novel therapeutic target in the treatment of solid-organ and hematologic malignancies. CD47 is also expressed on RBCs. Here, we report our experience of the RBC effects and the impact on blood bank testing and transfusion management in a Phase 1 trial of the humanized anti-CD47 monoclonal antibody Hu5F9-G4 in relapsed or primary refractory acute myeloid leukemia (AML) (NCT02678338). STUDY DESIGN AND METHODS: Nineteen patients with relapsed or primary refractory AML treated across five UK centers were included for analysis. Patients received escalating doses of Hu5F9-G4. Serial laboratory data were collected to evaluate impact on hemoglobin (Hb), markers of hemolysis (bilirubin, lactate dehydrogenase, reticulocyte count), transfusion requirements, and blood compatibility testing. RESULTS: A decline in Hb was observed with drug administration (median Hb change, -1.0 g/dL; range, 0.4-1.6) with associated increase in transfusion requirements. Patients responded to transfusion with a median Hb increment per unit of 1.0 g/dL. RBC agglutination was seen in all cases without associated change in Hb, lactate dehydrogenase, bilirubin, or reticulocyte count. Nine of 19 (47%) patients developed a newly positive antibody screen with a pan-agglutinin identified in plasma. Invalid ABO blood grouping occurred in 4 of 12 (33%) non-group O patients due to anomalous reactivity in the reverse ABO-type results. CONCLUSIONS: Treatment with Hu5F9-G4 in patients with AML resulted in an Hb decline and increased transfusion requirements. Problems with ABO blood typing and compatibility testing were widely observed and should be expected by centers treating recipients of Hu5F9-G4.


Subject(s)
Antibodies, Monoclonal, Humanized/adverse effects , Blood Grouping and Crossmatching , Blood Transfusion , CD47 Antigen/antagonists & inhibitors , Erythrocytes/drug effects , Leukemia, Myeloid, Acute/immunology , Adult , Aged , Aged, 80 and over , Anemia/chemically induced , Antibodies, Monoclonal, Humanized/administration & dosage , Antibodies, Monoclonal, Humanized/pharmacology , Diagnostic Errors/prevention & control , Humans , Leukemia, Myeloid, Acute/therapy , Middle Aged , Neoplasm Recurrence, Local/therapy
2.
J Intern Med ; 283(4): 371-379, 2018 04.
Article in English | MEDLINE | ID: mdl-29214689

ABSTRACT

BACKGROUND: Disease recurrence remains the major cause of death in adults with acute myeloid leukaemia (AML) treated using either intensive chemotherapy (IC) or allogenic stem cell transplantation (allo-SCT). AIMS: The timely delivery of maintenance drug or cellular therapies represent emerging strategies with the potential to reduce relapse after both treatment modalities, but whilst the determinants of overall relapse risk have been extensively characterized the factors determining the timing of disease recurrence have not been characterized. MATERIALS AND METHODS: We have therefore examined, using a series of sequential landmark analyses, relapse kinetics in a cohort of 2028 patients who received an allo-SCT for AML in CR1 and separately 570 patients treated with IC alone. RESULTS: In the first 3 months after allo-SCT, the factors associated with an increased risk of relapse included the presence of the FLT3-ITD (P < 0.001), patient age (P = 0.012), time interval from CR1 to transplant (P < 0.001) and donor type (P = 0.03). Relapse from 3 to 6 months was associated with a higher white cell count at diagnosis (P = 0.001), adverse-risk cytogenetics (P < 0.001), presence of FLT3-ITD mutation (P < 0.001) and time interval to achieve first complete remission (P = 0.013). Later relapse was associated with adverse cytogenetics, mutated NPM1, absence of chronic graft-versus-host disease (GVHD) and the use of in vivo T-cell depletion. In patients treated with IC alone, the factors associated with relapse in the first 3 months were adverse-risk cytogenetics (P < 0.001) and FLT3-ITD status (P = 0.001). The factors predicting later relapse were the time interval from diagnosis to CR1 (P = 0.22) and time interval from CR1 to IC (P = 0.012). DISCUSSION AND CONCLUSION: Taken together, these data provide novel insights into the biology of disease recurrence after both allo-SCT and IC and have the potential to inform the design of novel maintenance strategies in both clinical settings.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Leukemia, Myeloid, Acute/therapy , Peripheral Blood Stem Cell Transplantation , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Nucleophosmin , Recurrence , Retrospective Studies , Transplantation, Homologous , Young Adult
3.
Arch Dis Child Fetal Neonatal Ed ; 101(1): F67-71, 2016 Jan.
Article in English | MEDLINE | ID: mdl-25956670

ABSTRACT

OBJECTIVE: To systematically review current evidence regarding prenatal diagnosis and management of transient abnormal myelopoiesis (TAM) in fetuses with trisomy 21. A novel case of GATA1-positive TAM, in which following serial in utero blood transfusion clinical improvement and postnatal remission were observed, is included. SEARCH STRATEGY AND DATA COLLECTION: A systematic search of electronic databases (inception to October 2014) and reference lists, hand-searching of journals and expert contact. All confirmed cases of prenatal TAM were included for analysis. Data on study characteristics, design and quality were obtained. RESULTS: Of 73 potentially relevant citations identified, 22 studies were included, describing 39 fetuses. All studies included comprised single case or small cohort studies; overall quality was 'very low'. Fetal/neonatal outcome was poor; 12 stillbirths (30.8%), 4 neonatal deaths (10.2%) and 7 infant deaths (17.9%). In two cases, the pregnancy was terminated (5.1%). TAM was primarily detected in the third trimester (79.4%), and in 14 a retrospective diagnosis was made postpartum. Ultrasound features indicative of TAM included hepatomegaly±splenomegaly (79.5%), hydrops fetalis (30.8%), pericardial effusion (23.1%) and aberrant liquor volume (15.4%). When performed, liver function tests were abnormal in 91.6% of cases. CONCLUSIONS: Prenatal TAM presents a challenging diagnosis, and prognosis is poor, with consistently high mortality. A low threshold to measure haematological and biochemical markers is advised when clinical features typical of TAM are detected in the context of trisomy 21. Larger prospective studies are warranted to accurately ascertain the role of GATA1 analysis and potential value of prenatal therapy.


Subject(s)
Down Syndrome/diagnosis , Leukemoid Reaction/diagnosis , Prenatal Diagnosis/methods , Adult , Down Syndrome/genetics , Down Syndrome/therapy , Female , Fetus , GATA1 Transcription Factor/genetics , Humans , Infant, Newborn , Leukemoid Reaction/genetics , Leukemoid Reaction/therapy , Pregnancy , Prognosis
5.
Indian J Med Microbiol ; 32(1): 19-25, 2014.
Article in English | MEDLINE | ID: mdl-24399382

ABSTRACT

PURPOSE: The aim of the study was to determine the genetic heterogeneity of Giardia intestinalis isolates detected in stool samples of the study population using polymerase chain reaction assay and restriction fragment length polymorphism. We also tried to correlate the association/differences between the clinical symptomatology and infection by different assemblages (genotypes) of G. intestinalis. MATERIALS AND METHODS: This cross-sectional study was conducted from April 2008 to June 2010. A total of 40 adults (n = 40) and 42 children (n = 42) below the age of 12 years with the clinical suspicion of giardiasis and with the onset of one or more of the following five symptoms, i.e., loose stool, nausea, weight loss, fatigue and foul smelling faeces and confirmed laboratory diagnosis of giardiasis at least once during the current episode of diarrhoea were included in this study. RESULTS: Of the 82 patients (males 66) enrolled in the study, 70 (85%) presented with diarrhoea (56 males) and 12 (15%) without diarrhoea (10 males). Out of 70 diarrheic patients, 61 (87%) had chronic diarrhoea, 8 (11.5%) had acute diarrhoea and 1 (1.5%) had persistent diarrhoea. Of the total patients, 63 (77%) were clinically assessed and were apparently immunocompetent, whereas, 19 (23%) immunocompromised patients had different underlying conditions besides giardiasis. Genotyping identified all 82 (100%) isolates as assemblage B. CONCLUSION: We found that assemblage B of G. intestinalis presents with all kinds of clinical features ranging from asymptomatic carriage to acute, persistent or chronic diarrhoea.


Subject(s)
Giardia lamblia/classification , Giardia lamblia/genetics , Giardiasis/parasitology , Adult , Child , Child, Preschool , Cross-Sectional Studies , DNA, Protozoan/genetics , Female , Genotype , Giardia lamblia/isolation & purification , Giardiasis/epidemiology , Giardiasis/pathology , Humans , India/epidemiology , Infant , Infant, Newborn , Male , Molecular Epidemiology , Polymerase Chain Reaction , Tertiary Care Centers
6.
Leukemia ; 28(6): 1259-70, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24336126

ABSTRACT

Transient leukemia (TL) is evident in 5-10% of all neonates with Down syndrome (DS) and associated with N-terminal truncating GATA1 mutations (GATA1s). Here we report that TL-cell clones generate abundant eosinophils in a substantial fraction of patients. Sorted eosinophils from patients with TL and eosinophilia carried the same GATA1s mutations as sorted TL blasts, consistent with their clonal origin. TL blasts exhibited a genetic program characteristic of eosinophils and differentiated along the eosinophil lineage in vitro. Similarly, ectopic expression of Gata1s, but not Gata1, in wild-type CD34(+)-hematopoietic stem and progenitor cells induced hyperproliferation of eosinophil promyelocytes in vitro. Although GATA1s retained the function of GATA1 to induce eosinophil genes by occupying their promoter regions, GATA1s was impaired in its ability to repress oncogenic MYC and the pro-proliferative E2F transcription network. Chromatin Immunoprecipitation Sequencing (ChIP-seq) indicated reduced GATA1s occupancy at the MYC promoter. Knockdown of MYC, or the obligate E2F-cooperation partner DP1, rescued the GATA1s-induced hyperproliferative phenotype. In agreement, terminal eosinophil maturation was blocked in Gata1(Δe2) knockin mice, exclusively expressing Gata1s, leading to accumulation of eosinophil precursors in blood and bone marrow. These data suggest a direct relationship between the N-terminal truncating mutations of GATA1 and clonal eosinophilia in DS patients.


Subject(s)
Cell Proliferation , Down Syndrome/pathology , Eosinophilia/pathology , GATA1 Transcription Factor/genetics , Leukemia, Myeloid, Acute/pathology , Mutation/genetics , Animals , Apoptosis , Cell Differentiation , Down Syndrome/complications , Down Syndrome/genetics , Eosinophilia/etiology , Hematopoietic Stem Cells/metabolism , Hematopoietic Stem Cells/pathology , Humans , Infant , Infant, Newborn , Leukemia, Myeloid, Acute/complications , Leukemia, Myeloid, Acute/genetics , Mice , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured
7.
Leuk Res Rep ; 2(2): 70-4, 2013.
Article in English | MEDLINE | ID: mdl-24371786

ABSTRACT

Patients with high risk myelodysplasia (HR-MDS) and acute myeloid leukaemia (AML) with chromosomal changes involving deletion of the long arm of chromosome 5 (del5q), especially with complex karyotype, rarely have a durable response to combination chemotherapy. In the subgroup with monosomal karyotype there are no long term survivors (Fang et al., 2011) [1]. Recent experience indicates that the incidence of del5q in AML is ~20-30%, with only 20-25% of patients achieving complete remission (CR) (Farag et al., 2006) [2]. Additionally, therapy has significant toxicity, with induction death rates ~20% even in younger patients (Juliusson et al., 2009) [3]. This lack of efficacy provides the clinical rationale for combination/sequential therapy with Lenalidomide and combination chemotherapy. Dose dependent haematological toxicity is the major safety concern with such a combination protocol. Therefore we conducted a phase 2 study, AML Len5 (ISRCTN58492795), to assess safety, tolerability and efficacy of lenalidomide monotherapy, followed by lenalidomide with intensive chemotherapy in patients with primary/relapsed/refractory high risk MDS or AML with abnormalities of chromosome 5.

8.
Leukemia ; 27(5): 1028-36, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23223186

ABSTRACT

Epigenetic therapies demonstrate significant clinical activity in acute myeloid leukemia (AML) and myelodysplasia (MDS) and constitute an important new class of therapeutic agents. However hematological responses are not durable and disease relapse appears inevitable. Experimentally, leukemic stem/progenitor cells (LSC) propagate disease in animal models of AML and it has been postulated that their relative chemo-resistance contributes to disease relapse. We serially measured LSC numbers in patients with high-risk AML and MDS treated with 5'-azacitidine and sodium valproate (VAL-AZA). Fifteen out of seventy-nine patients achieved a complete remission (CR) or complete remission with incomplete blood count recovery (CRi) with VAL-AZA therapy. There was no significant reduction in the size of the LSC-containing population in non-responders. While the LSC-containing population was substantially reduced in all patients achieving a CR/CRi it was never eradicated and expansion of this population antedated morphological relapse. Similar studies were performed in seven patients with newly diagnosed AML treated with induction chemotherapy. Eradication of the LSC-containing population was observed in three patients all of whom achieved a durable CR in contrast to patients with resistant disease where LSC persistence was observed. LSC quantitation provides a novel biomarker of disease response and relapse in patients with AML treated with epigenetic therapies. New drugs that target this cellular population in vivo are required.


Subject(s)
Antimetabolites, Antineoplastic/pharmacology , Azacitidine/pharmacology , Leukemia, Myeloid, Acute/drug therapy , Myelodysplastic Syndromes/drug therapy , Neoplastic Stem Cells/drug effects , Adult , Aged , Aged, 80 and over , Female , Humans , Immunophenotyping , Induction Chemotherapy , Leukemia, Myeloid, Acute/mortality , Leukemia, Myeloid, Acute/pathology , Male , Middle Aged , Myelodysplastic Syndromes/mortality , Myelodysplastic Syndromes/pathology , Neoplastic Stem Cells/immunology , Prognosis
9.
Eur Rev Med Pharmacol Sci ; 16(4): 530-2, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22696882

ABSTRACT

BACKGROUND: Oral submucous fibrosis (OSMF) is a crippling slowly progressive disease of oral cavity that predominantly affects people habit of consuming areca nut and its commercial preparations which generates high levels of reactive oxygen species (ROS) during their metabolism. OBJECTIVE: The objective of this present study is to evaluate the role of oxidative stress in causation and progression of OSMF by measuring the levels of nonenzymatic antioxidants in OSMF patients. MATERIALS AND METHODS: For this study we selected 27 newly diagnosed OSMF patients of both sex with age group between 23 to 40 years and the same number of age and sex matched healthy individuals were selected as control group. In both the groups we measured plasma non enzymatic antioxidants like vitamin A. E, C and reduced glutathione. Total antioxidant activity was also assessed in both the groups. RESULTS AND CONCLUSIONS: We observed a very low levels of plasma non-enzymatic antioxidants (p < 0.001) and at the same time a very poor antioxidant activity (p < 0.001) in OSMF patients when compared to controls. Therefore, consumption of tobacco or areca quid creates an oxidative stress environment which might plays a major role in the causation of OSMF.


Subject(s)
Antioxidants/analysis , Glutathione/blood , Mouth Neoplasms/blood , Oral Submucous Fibrosis/blood , Oxidative Stress , Precancerous Conditions/blood , Vitamin A/blood , Vitamin E/blood , beta Carotene/blood , Adult , Areca , Biomarkers/blood , Case-Control Studies , Disease Progression , Down-Regulation , Female , Humans , India , Male , Mastication , Mouth Neoplasms/etiology , Nuts/adverse effects , Oral Submucous Fibrosis/etiology , Precancerous Conditions/etiology , Young Adult
10.
N Engl J Med ; 365(15): 1384-95, 2011 Oct 13.
Article in English | MEDLINE | ID: mdl-21995386

ABSTRACT

BACKGROUND: Myelodysplastic syndromes are a diverse and common group of chronic hematologic cancers. The identification of new genetic lesions could facilitate new diagnostic and therapeutic strategies. METHODS: We used massively parallel sequencing technology to identify somatically acquired point mutations across all protein-coding exons in the genome in 9 patients with low-grade myelodysplasia. Targeted resequencing of the gene encoding RNA splicing factor 3B, subunit 1 (SF3B1), was also performed in a cohort of 2087 patients with myeloid or other cancers. RESULTS: We identified 64 point mutations in the 9 patients. Recurrent somatically acquired mutations were identified in SF3B1. Follow-up revealed SF3B1 mutations in 72 of 354 patients (20%) with myelodysplastic syndromes, with particularly high frequency among patients whose disease was characterized by ring sideroblasts (53 of 82 [65%]). The gene was also mutated in 1 to 5% of patients with a variety of other tumor types. The observed mutations were less deleterious than was expected on the basis of chance, suggesting that the mutated protein retains structural integrity with altered function. SF3B1 mutations were associated with down-regulation of key gene networks, including core mitochondrial pathways. Clinically, patients with SF3B1 mutations had fewer cytopenias and longer event-free survival than patients without SF3B1 mutations. CONCLUSIONS: Mutations in SF3B1 implicate abnormalities of messenger RNA splicing in the pathogenesis of myelodysplastic syndromes. (Funded by the Wellcome Trust and others.).


Subject(s)
Myelodysplastic Syndromes/genetics , Phosphoproteins/genetics , Point Mutation , Ribonucleoprotein, U2 Small Nuclear/genetics , Erythrocytes/pathology , Gene Expression Profiling , High-Throughput Nucleotide Sequencing , Humans , Phenotype , RNA Splicing Factors
11.
J Thromb Haemost ; 9(8): 1572-81, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21668739

ABSTRACT

BACKGROUND: Transcription factors are essential for blood cell formation. Mice expressing low levels of c-Myb (c-Myb(low)) have an increased number of bone marrow megakaryocytes (MKs) and corresponding thrombocytosis. In contrast, mice engineered to express low levels of GATA-1 (GATA-1(low)) in the megakaryocytic lineage exhibit aberrant megakaryocytopoiesis with hyperproliferation of progenitors and defective terminal differentiation leading to thrombocytopenia. These seemingly opposite roles may affect platelet turnover and thus be of clinical relevance. OBJECTIVE: To determine how these two transcription factors act together to control megakaryocytopoiesis and platelet formation. METHODS: We used a combination of cellular and molecular in vitro assays to examine the ability of bone marrow cells from mice expressing low levels of both c-Myb and GATA-1 (referred to as double(low)) to produce MKs and platelets. RESULTS: Double(low) cells, or those with low GATA-1 levels in which c-Myb is conditionally deleted, lack the hyperproliferative capacity of GATA-1(low) cells, allowing the cells to proceed towards more committed MKs that are, however, impaired in their capacity to produce fully differentiated cells, as confirmed by the abundance of morphologically aberrant cells that lack the ability to form proplatelets. CONCLUSION: c-Myb and GATA-1 act in concert to achieve correct megakaryocytic differentiation. GATA-1 regulates both the proliferation of megakaryocytic progenitors and their terminal maturation. c-Myb also acts at the level of the progenitor by influencing its commitment to differentiation, but in contrast to GATA-1 it does not have any effect on the process of terminal differentiation.


Subject(s)
Blood Platelets/metabolism , GATA1 Transcription Factor/metabolism , Megakaryocytes/metabolism , Proto-Oncogene Proteins c-myb/metabolism , Signal Transduction , Thrombopoiesis , Animals , Cell Differentiation , Cell Lineage , Cell Proliferation , Cells, Cultured , GATA1 Transcription Factor/deficiency , GATA1 Transcription Factor/genetics , Mice , Mice, Knockout , Myelodysplastic Syndromes/blood , Myelodysplastic Syndromes/genetics , Proto-Oncogene Proteins c-myb/deficiency , Proto-Oncogene Proteins c-myb/genetics , Signal Transduction/genetics , Thrombocytopenia/blood , Thrombocytopenia/genetics , Thrombocytosis/blood , Thrombocytosis/genetics
12.
J AOAC Int ; 93(2): 622-7, 2010.
Article in English | MEDLINE | ID: mdl-20480910

ABSTRACT

An AOAC collaborative study was conducted to evaluate an affinity LC procedure for measuring immunoglobulin G (IgG) in selected dairy powders. The powders were extracted with 0.15 M sodium chloride solution and the pH was adjusted to 4.6 to precipitate caseins, which would otherwise lead to an overestimation of IgG. The analyte was then bound to a commercially available Protein G affinity cartridge and selectively eluted with a glycine buffer at pH 2.5. Detection was at 280 nm and quantification was made against a calibration curve prepared from bovine serum IgG. The samples analyzed included the likely matrixes for which this assay will find commercial use, namely, high- and low-protein-content colostrum powders, tablets containing colostrum powder, and some IgG-containing dairy powders; milk protein isolate, whey protein concentrate, and skim milk powder. Eleven laboratories provided data for the study and assayed blind duplicates of six materials. The repeatability RSD values ranged from 2.1 to 4.2% and the reproducibility RSD values ranged from 6.4 to 18.5%. The Protein G method with casein removal has adequate reproducibility for measuring IgG in colostrum-derived powders that are traded on the basis of IgG content as a colostral marker.


Subject(s)
Chemistry Techniques, Analytical , Chromatography, Liquid/methods , Colostrum/metabolism , Immunoglobulin G/analysis , Milk/metabolism , Nerve Tissue Proteins/chemistry , Animals , Biomarkers , Calibration , Cattle , Hydrogen-Ion Concentration , Immunoglobulin G/chemistry , Powders , Reproducibility of Results , Time Factors
13.
Indian J Microbiol ; 49(2): 128-33, 2009 Jun.
Article in English | MEDLINE | ID: mdl-23100761

ABSTRACT

The ITS region sequence of a phosphate-solubilizing fungus isolated from the rhizosphere of tea growing in Kangra valley of Himachal Pradesh showed 96% identity with Discosia sp. strain HKUCC 6626 ITS 1, 5.8S rRNA gene and ITS 2 complete sequence, and 28S rRNA gene partial sequence. The fungus exhibited the multiple plant growth promoting attributes of solubilization of inorganic phosphate substrates, production of phytase and siderophores, and biosynthesis of indole acetic acid (IAA)-like auxins. The fungal inoculum significantly increased the root length, shoot length and dry matter in the test plants of maize, pea and chickpea over the uninoculated control under the controlled environment. The plant growth promoting attributes have not been previously studied for the fungus. The fungal strain with its multiple plant growth promoting activities appears attractive towards the development of microbial inoculants.

16.
Lett Appl Microbiol ; 36(3): 129-34, 2003.
Article in English | MEDLINE | ID: mdl-12581369

ABSTRACT

AIMS: To develop a novel, rapid and effective screening method for chitinase producing bacteria. METHODS AND RESULTS: A simple and rapid technique for screening of potential chitinolytic bacteria has been developed using the chitin binding dye calcofluor white M2R in chitin agar. Microorganisms possessing high chitinolytic potential gave a clear zone under ultraviolet light after 24-48 h of incubation. This method was successfully applied for isolating the hyperchitinase mutant of Alcaligenes xylosoxydans. The mutant Alc. xylosoxydans EMS 33 was found to produce 3.4 times more chitinase than the wild type. CONCLUSIONS: In this study, the screening method for chitinase producing bacteria has been developed and it was applied to screen chitinase-overproducing mutant of Alc. xylosoxydans. SIGNIFICANCE AND IMPACT OF THE STUDY: The novel screening method for chitinase producer is more sensitive, rapid, user-friendly and reliable, which can also be used for screening of recombinants having chitinase gene.


Subject(s)
Alcaligenes/enzymology , Bacteria/enzymology , Bacteriological Techniques , Chitin/metabolism , Chitinases/metabolism , Alcaligenes/genetics , Alcaligenes/isolation & purification , Alcaligenes/radiation effects , Bacteria/drug effects , Bacteria/isolation & purification , Benzenesulfonates/chemistry , Benzenesulfonates/pharmacology , Chitin/chemistry , Chitin/isolation & purification , Colony Count, Microbial , Mutation , Sensitivity and Specificity
17.
J Colloid Interface Sci ; 257(1): 127-34, 2003 Jan 01.
Article in English | MEDLINE | ID: mdl-16256464

ABSTRACT

Heterogeneous ion-exchange membranes (both cationic and anionic types) have been synthesized by solution casting techniques using polyvinyl chloride (PVC) as binder and ion-exchange resin (-300+400 mesh). The binder:resin ratio varied from 60:40 to 30:70. The transport behavior of the membranes has been evaluated chronopotentiometrically in sodium chloride (NaCl) solutions of different concentrations. The different parameters E(0) (potential drop across the membrane at the instant of application of current I), E(max) (maximum potential drop across the membrane after the application of current I), DeltaE (magnitude of the potential jump across the membrane at transition time tau), Itau(1/2), tau, etc., have been evaluated. The isoconductance points were determined and based on the microheterogeneous model proposed by Zabolotsky and Nikonenko (J. Membrane Sci. 79 (1993) 181) the distribution factors beta has been evaluated for both types of ion exchange membranes. The electroconductivity of the joint gel (kappa ) and pure gel phases (kappa ' ) has been determined. At any particular solution concentration the transport number as well as the permselectivity of membranes increases with increased resin content of the membrane. The microheterogeneity factor beta exhibits synchronization among the each set of four different membranes for both the cationic and anionic type.

18.
Indian J Exp Biol ; 41(12): 1469-72, 2003 Dec.
Article in English | MEDLINE | ID: mdl-15320506

ABSTRACT

Alcaligenes xylosoxydans protected pigeonpea from Fusarium wilt in a pot experiment and field trials. When seeds of pigeonpea (C. cajan) were treated with A. xylosoxydans and sown in soil infested with Fusarium, the incidence of wilt was reduced by 43.5% and resulted in 58% higher grain yield. The antifungal activity of A. xylosoxydans was based on chitinase production and was comparable in efficacy to commercial antifungal agents such as benlate, monitor WP, thiram and bavistin.


Subject(s)
Alcaligenes/physiology , Cajanus/growth & development , Chitin/metabolism , Fusarium/physiology , Pest Control, Biological , Hydrolysis
19.
J Colloid Interface Sci ; 246(2): 366-71, 2002 Feb 15.
Article in English | MEDLINE | ID: mdl-16290424

ABSTRACT

The variations of the selectivity coefficient K(A)(B) between Na(+)-H(+), Na(+)-K(+), and Na(+)-Cu(2+) systems and the separation factor alpha(A)(B) between Na(+)-Cu(2+) and K(+)-Cu(2+) systems in cation-exchange membranes as functions of loading and particle size of resin have been measured. The exchange affinities of all the membranes increase as H(+)

20.
Pediatr Radiol ; 31(11): 814-6, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11692241

ABSTRACT

Ventriculoperitoneal shunts have been associated with many different complications. We describe two rare complications in a 10-month-old girl. To the best of our knowledge, protrusion of ventriculoperitoneal shunt through the knee has not been reported before.


Subject(s)
Foreign-Body Migration/diagnostic imaging , Knee , Sepsis/etiology , Ventriculoperitoneal Shunt/adverse effects , Diagnosis, Differential , Female , Humans , Infant , Sepsis/microbiology , Serratia marcescens/isolation & purification , Tomography, X-Ray Computed
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