Publications by authors named "Irina Kalinina"

23 Publications

  • Page 1 of 1

Platelet function and bleeding at different phases of childhood immune thrombocytopenia.

Sci Rep 2021 Apr 30;11(1):9401. Epub 2021 Apr 30.

National Medical Research Center of Pediatric Hematology, Oncology and Immunology Named After Dmitry Rogachev, Russian Ministry of Healthcare, 1 Samory Mashela Str, Moscow, Russia, 117997.

Immune thrombocytopenia (ITP) is believed to be associated with platelet function defects. However, their mechanisms are poorly understood, in particular with regard to differences between ITP phases, patient age, and therapy. We investigated platelet function and bleeding in children with either persistent or chronic ITP, with or without romiplostim therapy. The study included 151 children with ITP, of whom 56 had disease duration less than 12 months (grouped together as acute/persistent) and 95 were chronic. Samples of 57 healthy children were used as controls, while 5 patients with leukemia, 5 with aplastic anemia, 4 with MYH9-associated thrombocytopenia, and 7 with Wiskott-Aldrich syndrome were used as non-ITP thrombocytopenia controls. Whole blood flow cytometry revealed that platelets in both acute/persistent and chronic ITP were increased in size compared with healthy donors. They were also pre-activated as assessed by PAC1, CD62p, cytosolic calcium, and procoagulant platelet levels. This pattern was not observed in other childhood thrombocytopenias. Pre-activation by CD62p was higher in the bleeding group in the chronic ITP cohort only. Romiplostim treatment decreased size and pre-activation of the patient platelets, but not calcium. Our data suggest that increased size, pre-activation, and cytosolic calcium are common for all ITP platelets, but their association with bleeding could depend on the disease phase.
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http://dx.doi.org/10.1038/s41598-021-88900-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8087794PMC
April 2021

GATA1 mutation analysis and molecular landscape characterization in acute myeloid leukemia with trisomy 21 in pediatric patients.

Int J Lab Hematol 2021 Jan 2. Epub 2021 Jan 2.

Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia.

Introduction: Accurate detection of GATA1 mutation is highly significant in patients with acute myeloid leukemia (AML) and trisomy 21 as it allows optimization of clinical protocol. This study was aimed at (a) enhanced search for GATA1 mutations; and (b) characterization of molecular landscapes for such conditions.

Methods: The DNA samples from 44 patients with newly diagnosed de novo AML with trisomy 21 were examined by fragment analysis and Sanger sequencing of the GATA1 exon 2, complemented by targeted high-throughput sequencing (HTS).

Results: Acquired GATA1 mutations were identified in 43 cases (98%). Additional mutations in the genes of JAK/STAT signaling, cohesin complex, and RAS pathway activation were revealed by HTS in 48%, 36%, and 16% of the cases, respectively.

Conclusions: The GATA1 mutations were reliably determined by fragment analysis and/or Sanger sequencing in a single PCR amplicon manner. For patients with extremely low blast counts and/or rare variants, the rapid screening with simple molecular approaches must be complemented with HTS. The JAK/STAT and RAS pathway-activating mutations may represent an extra option of targeted therapy with kinase inhibitors.
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http://dx.doi.org/10.1111/ijlh.13451DOI Listing
January 2021

Outcome of αβ T cell-depleted transplantation in children with high-risk acute myeloid leukemia, grafted in remission.

Bone Marrow Transplant 2020 01 15;55(1):256-259. Epub 2019 Apr 15.

Department of Hematopoietic Stem Cell Transplantation, Dmitriy Rogachev National Medical Research Сenter of Pediatric Hematology, Oncology and Immunology, Samory Mashela street, 1, Moscow, 117997, Russia.

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http://dx.doi.org/10.1038/s41409-019-0531-3DOI Listing
January 2020

Thrombopoietin receptor agonist switch in children with persistent and chronic severe immune thrombocytopenia: A retrospective analysis in a large tertiary center.

Pediatr Blood Cancer 2019 06 11;66(6):e27704. Epub 2019 Mar 11.

Dmitri Rogachev National Research Center for Pediatric Hematology, Oncology and Immunology, Moskva, Russia.

We retrospectively analyzed sequential therapy with romiplostim and eltrombopag in 23 children with immune thrombocytopenia: switching from romiplostim to eltrombopag (10 patients) or vice versa (13 patients). The median age of patients at enrollment in the study was 5.6 years (2-15 years). Switching from romiplostim to eltrombopag was effective in eight (80%) patients, whereas switching from eltrombopag to romiplostim was effective in eight (62%) patients. The response rate was similar in patients failing the first thrombopoietin receptor agonist and those who had previous response. To date, all responders continue to maintain platelets over 50 × 10 /L at 13-39 months after switching.
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http://dx.doi.org/10.1002/pbc.27704DOI Listing
June 2019

αβ T Cell-Depleted Haploidentical Hematopoietic Stem Cell Transplantation without Antithymocyte Globulin in Children with Chemorefractory Acute Myelogenous Leukemia.

Biol Blood Marrow Transplant 2019 05 21;25(5):e179-e182. Epub 2019 Jan 21.

Department of Hematopoietic Stem Cell Transplantation, Dmitriy Rogachev National Medical Research Center of Pediatric Hematology, Oncology, and Immunology, Moscow, Russia. Electronic address:

We evaluated the outcome of αβ T cell-depleted haploidentical hematopoietic stem cell transplantation (HSCT) in a cohort of children with chemorefractory acute myelogenous leukemia (AML). Twenty-two patients with either primary refractory (n = 10) or relapsed refractory (n = 12) AML in active disease status received a transplant from haploidentical donors. The preparative regimen included cytoreduction with fludarabine and cytarabine and subsequent myeloablative conditioning with treosulfan and thiotepa. Antithymocyte globulin was substituted with tocilizumab in all patients and also with abatacept in 10 patients. Grafts were peripheral blood stem cells engineered by αβ T cell and CD19 depletion. Post-transplantation prophylactic therapy included infusion of donor lymphocytes, composed of a CD45RA-depleted fraction with or without a hypomethylating agent. Complete remission was achieved in 21 patients (95%). The cumulative incidence of grade II-IV acute graft-versus-host disease (GVHD) was 18%, and the cumulative incidence of chronic GVHD was 23%. At 2 years, transplantation-related mortality was 9%, relapse rate was 42%, event-free survival was 49%, and overall survival was 53%. Our data suggest that αβ T cell-depleted haploidentical HSCT provides a reasonable chance of long-term survival in a cohort of children with chemorefractory AML and creates a solid basis for further improvement.
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http://dx.doi.org/10.1016/j.bbmt.2019.01.023DOI Listing
May 2019

Molecular characteristic of acute leukemias with t(16;21)/FUS-ERG.

Ann Hematol 2018 Jun 9;97(6):977-988. Epub 2018 Feb 9.

Dmitry Rogachev Research and Clinical Center for Pediatric Hematology, Oncology and Immunology, Samora Mashela str., 1, Moscow, 117997, Russia.

T(16;21)(p11;q22)/FUS-ERG is a rare but recurrent translocation in acute leukemias and in some types of solid tumors. Due to multiple types of FUS-ERG transcripts, PCR-based minimal residual disease detection is impeded. In this study, we evaluated a cohort of pediatric patients with t(16;21)(p11;q22)/FUS-ERG and revealed fusion gene breakpoints. We implemented next-generation sequencing (NGS) on long PCR amplicons for the detection of fusion genes with unknown partners or DNA breakpoints. That allowed us to describe different fusion variants of FUS/ERG in different patients and to detect MRD on both RNA and DNA levels. We also found several accompanying mutations in epigenetic regulators (DNMT3A, ASXL1, BCOR) by targeted NGS approach in AML cases. These mutations preceded full transformation by t(16;21)(p11;q22)/FUS-ERG and allowed us to trace clonal evolution on all steps of therapy. As a casual observation, the ASXL1 mutation was found in the unrelated donor hematopoietic cells.
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http://dx.doi.org/10.1007/s00277-018-3267-zDOI Listing
June 2018

Control of thrombotic thrombocytopenic purpura by sirolimus in a child with juvenile myelomonocytic leukemia and somatic N-RAS mutation.

Pediatr Blood Cancer 2014 Oct 3;61(10):1871-3. Epub 2014 Mar 3.

Federal Research Center for Pediatric Hematology, Oncology and Immunology, Moscow, Russia.

We describe an infant who developed juvenile myelomonocytic leukemia (JMML) at the age of 6 months. Myeloproliferation was effectively controlled by low-dose cytosine arabinoside and 13-cis retinoic acid therapy. Two years after therapy for JMML was stopped, at the age of 5 years, the patient developed autoimmune thrombotic thrombocytopenic purpura (TTP). TTP was transiently controlled by plasma exchange, prednisolone, rituximab, and cyclophosphamide, but relapsed within a short time. Long-term control of TTP was established by sirolimus. Somatic N-RAS G38A→Gly13Asp substitution was restricted to hematopoietic cells. The somatic N-RAS mutation may link myeloproliferation and autoimmunity.
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http://dx.doi.org/10.1002/pbc.25013DOI Listing
October 2014

Cyclic tungstoselenites based on {Se2W12} units.

Inorg Chem 2014 Feb 5;53(4):2076-82. Epub 2014 Feb 5.

Nikolaev Institute of Inorganic Chemistry , Prospekt Lavrentyeva 3, 630090 Novosibirsk, Russia.

The reaction of Na2WO4 and SeO2 under moderately acidic conditions yielded a novel 39-tungsto-6-selenite, [(Se2W12O46(WO(H2O))3](24-) (1), isolated as Na24[H6Se6W39O144]·74H2O. The macrocyclic polyanion consists of three {Se2W12} fragments connected via three trans-{WO(H2O)}(4+) groups. The same {Se2W12} building block is present in the structure of [(Se2W12O46)2{Mn2Cl(H2O)2}{Mn(H2O)2}2(SeO)2](13-) (2), which was obtained from the same reagents in the presence of MnCl2. The compounds were characterized by single-crystal X-ray diffraction, (77)Se NMR, Fourier transform infrared, and Raman spectroscopy.
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http://dx.doi.org/10.1021/ic402668vDOI Listing
February 2014

Chemically functionalized single-walled carbon nanotube films modulate the morpho-functional and proliferative characteristics of astrocytes.

Nano Lett 2013 Sep 19;13(9):4387-92. Epub 2013 Aug 19.

Departments of Neurobiology and Biomedical Engineering, University of Alabama , Birmingham, Alabama 35294, United States.

We used single-walled carbon nanotube (CNT) films to modulate the morpho-functional and proliferative characteristics of astrocytes. When plated on the CNT films of various thicknesses, astrocytes grow bigger and rounder in shape with a decrease in the immunoreactivity of glial fibrillary acidic protein along with an increase in their proliferation, changes associated with the dedifferentiation of astrocytes in culture. Thus, CNT films, as a coating material for electrodes used in brain machine interface, could reduce astrogliosis around the site of implantation.
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http://dx.doi.org/10.1021/nl402226zDOI Listing
September 2013

NPM1, FLT3, and c-KIT mutations in pediatric acute myeloid leukemia in Russian population.

J Pediatr Hematol Oncol 2013 Apr;35(3):e100-8

Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia.

We evaluated frequencies of NPM1, FLT3, c-KIT mutations in childhood acute myeloid leukemia (AML) in Russia and assessed prognostic relevance of the mutations. RNA and DNA were extracted from bone marrow samples of 186 (106 male and 80 female) pediatric patients younger than 17 year with de novo AML. Mutations and chromosomal rearrangements were detected by sequencing of a corresponding gene. NPM1 mutations were found in 5.2%, FLT3 mutations in 12.1%, c-KIT mutations in 3.7% of the patients. NPM1 mutations were associated with the absence of chromosomal aberrations (P=0.007) and FLT3/ITD (P=0.018). New data on incidence of c-KIT mutations in various AML subtypes as well as new variations of c-KIT mutations in the exon 8 are presented. The results are compared to previously published studies on NPM1, FLT3, c-KIT mutations in various populations. No statistically significant differences in survival rates between groups with or without of FLT3, NPM1, c-KIT mutations were found (P>0.05). Meanwhile, 4-year overall survival rates were higher in patients having NPM1 mutations comparing with NPM1/WT patients (100% vs. 50%) and in patients having FLT3 mutations comparing with FLT3/WT patients (70% vs. 50%). The data presented contribute to knowledge on incidence and prognostic significance of the mutations in pediatric AML.
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http://dx.doi.org/10.1097/MPH.0b013e318286d261DOI Listing
April 2013

Effect of covalent chemistry on the electronic structure and properties of carbon nanotubes and graphene.

Acc Chem Res 2013 Jan 1;46(1):65-76. Epub 2012 Nov 1.

Center for Nanoscale Science & Engineering, University of California, Riverside, 92521, United States.

In this Account, we discuss the chemistry of graphitic materials with particular reference to three reactions studied by our research group: (1) aryl radical addition, from diazonium precursors, (2) Diels-Alder pericyclic reactions, and (3) organometallic complexation with transition metals. We provide a unified treatment of these reactions in terms of the degenerate valence and conduction bands of graphene at the Dirac point and the relationship of their orbital coefficients to the HOMO and LUMO of benzene and to the Clar structures of graphene. In the case of the aryl radical addition and the Diels-Alder reactions, there is full rehybridization of the derivatized carbon atoms in graphene from sp(2) to sp(3), which removes these carbon atoms from conjugation and from the electronic band structure of graphene (referred to as destructive rehybridization). The radical addition process requires an electron transfer step followed by the formation of a σ-bond and the creation of a π-radical in the graphene lattice, and thus, there is the potential for unequal degrees of functionalization in the A and B sublattices and the possibility of ferromagnetism and superparamagnetism in the reaction products. With regard to metal functionalization, we distinguish four limiting cases: (a) weak physisorption, (b) ionic chemisorption, in which there is charge transfer to the graphitic structure and preservation of the conjugation and band structure, (c) covalent chemisorption, in which there is strong rehybridization of the graphitic band structure, and (d) covalent chemisorption with formation of an organometallic hexahapto-metal bond that largely preserves the graphitic band structure (constructive rehybridization). The constructive rehybridization that accompanies the formation of bis-hexahapto-metal bonds, such as those in (η(6)-SWNT)Cr(η(6)-SWNT), interconnects adjacent graphitic surfaces and significantly reduces the internanotube junction resistance in single-walled carbon nanotube (SWNT) networks. The conversion of sp(2) hybridized carbon atoms to sp(3) can introduce a band gap into graphene, influence the electronic scattering, and create dielectric regions in a graphene wafer. However, the organometallic hexahapto (η(6)) functionalization of the two-dimensional (2D) graphene π-surface with transition metals provides a new way to modify graphitic structures that does not saturate the functionalized carbon atoms and, by preserving their structural integrity, maintains the delocalization in these extended periodic π-electron systems and offers the possibility of three-dimensional (3D) interconnections between adjacent graphene sheets. These structures may find applications in interconnects, 3D-electronics, organometallic catalysis, atomic spintronics and in the fabrication of new electronic materials.
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http://dx.doi.org/10.1021/ar300177qDOI Listing
January 2013

Chemically functionalized water-soluble single-walled carbon nanotubes modulate morpho-functional characteristics of astrocytes.

Nano Lett 2012 Sep 30;12(9):4742-7. Epub 2012 Aug 30.

Department of Neurobiology, University of Alabama, Birmingham, Alabama 35294, United States.

We report the use of chemically functionalized water-soluble single-walled carbon nanotubes (ws-SWCNTs) for the modulation of morpho-functional characteristics of astrocytes. When added to the culturing medium, ws-SWCNTs were able to make astrocytes larger and stellate/mature, changes associated with the increase in glial fibrillary acidic protein immunoreactivity. Thus, ws-SWCNTs could have more beneficial effects at the injury site than previously thought; by affecting astrocytes, they could provide for a more comprehensive re-establishment of the brain computational power.
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http://dx.doi.org/10.1021/nl302178sDOI Listing
September 2012

Bis[tetraruthenium(IV)]-containing polyoxometalates: [{Ru(IV)4O6(H2O)9}2Sb2W20O68(OH)2]4- and [{Ru(IV)4O6(H2O)9}2{Fe(H2O)2}2{β-TeW9O33}2H]-.

Inorg Chem 2012 Jul 2;51(14):7442-4. Epub 2012 Jul 2.

School of Engineering and Science, Jacobs University, P.O. Box 750 561, 28725 Bremen, Germany.

The reaction of [Sb(2)W(22)O(74)(OH)(2)](12-) and [Fe(4)(H(2)O)(10)(β-TeW(9)O(33))(2)](4-) with (NH(4))(2)[RuCl(6)] in aqueous solution resulted in the novel ruthenium(IV)-containing polyanions [{Ru(IV)(4)O(6)(H(2)O)(9)}(2)Sb(2)W(20)O(68)(OH)(2)](4-) and [{Ru(IV)(4)O(6)(H(2)O)(9)}(2){Fe(H(2)O)(2)}(2){β-TeW(9)O(33)}(2)H](-), exhibiting two cationic, adamantane-like, tetraruthenium(IV) units {Ru(4)O(6)(H(2)O)(9)}(4+) bound to the respective polyanion in an external, highly accessible fashion.
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http://dx.doi.org/10.1021/ic300849bDOI Listing
July 2012

Chemically engineered single-walled carbon nanotube materials for the electronic detection of hydrogen chloride.

Adv Mater 2010 Feb;22(7):848-52

Center for Nanoscale Science and Engineering, Department of Chemistry, University of California - Riverside, Riverside, California 92521, USA.

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http://dx.doi.org/10.1002/adma.200903427DOI Listing
February 2010

Functionalization and dissolution of nitric acid treated single-walled carbon nanotubes.

J Am Chem Soc 2009 Dec;131(50):18153-8

Department of Chemistry, and Center for Nanoscale Science and Engineering, University of California, Riverside, California 92521-0403, USA.

We report an investigation of the nature and chemical functionalization of nitric acid treated single-walled carbon nanotubes (SWNTs). SWNTs washed with diluted sodium hydroxide solutions were characterized by near-IR, mid-IR, and Raman spectroscopy as well as TEM, and the remaining carboxylic acid content was determined to assess the effect of base washing on the removal of carboxylated carbon fractions, which are generated by the nitric acid treatment. It was found that even after exhaustive washing with aqueous base the purified SWNTs contain carboxylic acid groups in sufficient quantity to prepare high quality soluble SWNT materials by covalent functionalization with octadecylamine.
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http://dx.doi.org/10.1021/ja906267gDOI Listing
December 2009

Incorporation of molybdenum sulfide cluster units into a dawson-like polyoxometalate structure to give hybrid polythiooxometalates.

Angew Chem Int Ed Engl 2008 ;47(8):1465-8

Nikolaev Institute of Inorganic Chemistry SB RAS, Prospect Lavrentyeva 3, 630090 Novosibirsk, Russia.

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http://dx.doi.org/10.1002/anie.200704344DOI Listing
March 2008

Heterometallic cuboidal clusters M(3)M'Q(4) (M = Mo, W; M'= Sn, Pb, As, Sb; Q = S, Se): from coordination compounds to supramolecular adducts.

Inorg Chem 2008 Jan 11;47(1):306-14. Epub 2007 Dec 11.

Departamento de Química InorgAnica, Universidad de La Laguna, 38200 La Laguna, Tenerife, Islas Canarias, Spain.

Reactions of the incomplete cuboidal clusters [M3Q4(acac)3(py)3]+ (M = Mo, W; Q = S, Se) with group 14 and 15 metal complexes with the s2p0 electronic configuration (AsPh3, SbPh3, SbCl3, SbI3, PbI3-, SnCl3-) led to heterometal incorporation with the formation of cuboidal clusters of the type [M3(EX3)Q4(acac)3(py)3]n+ (n = 0 for Sn, Pb; n = 1 for As, Sb), whose structures were determined by X-ray diffraction. The cuboidal clusters can be described as complexes of the cluster tridentate ligand [M3Q4(acac)3(py)3]+ (mu2-chalcogen atoms as donors) with the EX3, where the E atom attains a distorted octahedral coordination. Analysis based on the bond distances E-Q gives the following sequence of affinity: As < Sb; Pb < Sn approximately Sb; SbPh3 < SbI3 approximately SbCl3; W3S4 < W3Se4. Interaction energies at the gas phase between [W3Q4(acac)3(py)3]+ (Q = S, Se) and SbX3 (X = I, Ph) were computed at the DFT level (BP86/TZP). The magnitude of the interaction depends strongly on the substituents at Sb, and the replacement of iodine by the phenyl group decreases the interaction energy from -9.21 to -2.70 kcal/mol and from -12.73 to -3.85 kcal/mol for the W3SbS4 and W3SbSe4 cores, respectively.
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http://dx.doi.org/10.1021/ic701581uDOI Listing
January 2008

The preparation of new phosphorus-centered functional groups for modified oligonucleotides and other natural phosphates.

Molecules 2005 Sep 30;10(9):1048-73. Epub 2005 Sep 30.

Laboratoire des Fonctions Azotées et Oxygénées Complexes, IRCOF-Université de Rouen, Rue Tesnières, F-76821 Mont Saint Aignan, France.

Efforts to develop synthetic methodologies allowing the preparation of alpha,alpha- difluorophosphonothioates, alpha,alpha-difluorophosphonodithioates, alpha,alpha-difluorophosphono- trithioates, and alpha,alpha-difluorophosphinates are reviewed in the light of applications in the field of modified oligonucleotides and cyclitol phosphates. Two successful approaches have been developed, based either on the addition of phosphorus-centered radicals onto gem-difluoroalkenes or on a process involving the addition of lithiodifluorophosphono- thioates 91 onto a ketone and the subsequent deoxygenation reaction of the adduct. The radical route successfully developed a practical route to alpha,alpha-difluoro-H-phosphinates which proved to be useful intermediates to a variety of phosphate isosters. The ionic route led to the first preparation of phosphonodifluoromethyl analogues of nucleoside- 3'-phosphates.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6147685PMC
http://dx.doi.org/10.3390/10091048DOI Listing
September 2005

Mechanism of ammonia detection by chemically functionalized single-walled carbon nanotubes: in situ electrical and optical study of gas analyte detection.

J Am Chem Soc 2007 Sep 15;129(35):10700-6. Epub 2007 Aug 15.

Center for Nanoscale Science and Engineering, Department of Chemistry, University of California-Riverside, Riverside, California 92521, USA.

We provide definitive evidence for the mechanism of electronic detection of ammonia by monitoring in situ changes in the electrical resistance and optical spectra of films of poly(m-aminobenzenesulfonic acid)-functionalized SWNTs (SWNT-PABS). The increase of resistance during exposure to ammonia is associated with deprotonation of the PABS side chain that in turn induces electron transfer between the oligomer and the valence band of the semiconducting SWNTs. Near IR spectroscopy is used to demonstrate that the charge transfer is a weakly driven process, and this accounts for the high reversibility of the sensor. We show that the sensitivity of the chemiresistors increases as the film thickness is reduced to the percolation threshold and that the SWNT-PABS film thickness provides a simple means to enhance the electronic response.
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http://dx.doi.org/10.1021/ja0703271DOI Listing
September 2007

Synthesis, structure and reactivity of cuboidal-type cluster aqua complexes with W3PdS4 4+ core.

Dalton Trans 2007 Feb 13(5):550-7. Epub 2006 Dec 13.

Departamento de Química Inorgánica, Universidad de La Laguna, 38200 La Laguna, Tenerife, Spain.

The reaction of PdCl(2) with [W3S4(H2O)9]4+ in the presence of hypophosphorous acid in 2 M HCl gives cuboidal cluster [W3(PdCl)S4(H2O)9]3+ (1) which undergoes condensation and crystallises from Hpts solutions as edge-linked double cubane cluster [{W3PdS4(H2O)9}2](pts)(8).19H2O (pts = p-toluenesulfonate) (1'). The substitution of Cl- in (1) by different ligands was explored. The Pd atom in the cluster shows an exceptionally high reactivity in the isomerisation of the hydrophosphoryl H2P(O)(OH), HP(O)(OH)2, HPPh(O)(OH) and HPPh2(O) molecules into the corresponding hydroxo tautomers HP(OH)2, P(OH)3, PhP(OH)2 and Ph2P(OH) stabilised by coordination at Pd. The reactions were followed by UV-Vis spectrophotometry and 31P NMR. Formation constants of the 1 : 1 coordination of [M3(PdCl)S4(H2O)9]3+ (M = Mo, W) with HP(OH)2 and As(OH)3 were obtained. The structures of cucurbit[6]uril (C36H36N24O12, CUC[6]) adducts [W3(PdP(OH)3)S4(H2O)8Cl]-(C36H36N24O12)Cl3.12.5H2O (2), and [W3Pd(PhP(OH)2)S4(H2O)7Cl2]2(C36H36N24O12)Cl4.9H2O (3) were determined by single-crystal X-ray diffraction.
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http://dx.doi.org/10.1039/b613790cDOI Listing
February 2007

Nucleotides and nucleic acids: a source of inspiration for the development of new, phosphorus-centered functional groups.

Nucleic Acids Symp Ser (Oxf) 2006 (50):53-4

University of Rouen, Laboratoire des Fonctions Azotées et Oxygénées Complexes, UMR 6014 CNRS, IRCOF, rue Tesnières, Mont Saint Aignan, France.

Synthetic methodologies aiming at the creation of new phosphorus-centered functional groups are reported, as well as applications to the field of nucleotide chemistry. Thus, difluorophosphonothioate-based, ionic reagents 3b and 3d are shown to allow the stereocontrolled and efficient synthesis of phosphonodifluoromethyl analogues of nucleoside-3'-phosphates. An alternate, radical approach describes the use of hypophosphorous acid to stereoselectively link two furanosyl units in positions 3 and 5, and to provide an access to alpha,alpha-difluoro-H-phosphinates. These intermediates are shown to be precursors to the corresponding fluorinated phosphonic acids, phosphonothioic acids and variously substituted phosphinates.
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http://dx.doi.org/10.1093/nass/nrl027DOI Listing
August 2007

Synthesis and reactivity of W3Te74+ clusters and chalcogen exchange in the M3Q7 (M = Mo, W; Q = S, Se, Te) cluster family.

Inorg Chem 2005 Oct;44(22):8116-24

Nikolayev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk.

Heating WTe(2), Te, and Br(2) at 390 degrees C followed by extraction with KCN gives [W(3)Te(7)(CN)(6)](2-). Crystal structures of double salts Cs(3.5)K{[W(3)Te(7)(CN)(6)]Br}Br(1.5).4.5H(2)O (1), Cs(2)K(4){[W(3)Te(7)(CN)(6)](2)Cl}Cl.5H(2)O (2), and (Ph(4)P)(3){[W(3)Te(7)(CN)(6)]Br}.H(2)O (3) reveal short Te(2)...X (X = Cl, Br) contacts. Reaction of polymeric Mo(3)Se(7)Br(4) with KNCSe melt gives [Mo(3)Se(7)(CN)(6)](2-). Reactions of polymeric Mo(3)S(7)Br(4) and Mo(3)Te(7)I(4) with KNCSe melt (200-220 degrees C) all give as final product [Mo(3)Se(7)(CN)(6)](2)(-) via intermediate formation of [Mo(3)S(4)Se(3)(CN)(6)](2-)/[Mo(3)SSe(6)(CN)(6)](2-) and of [Mo(3)Te(4)Se(3)(CN)(6)](2-), respectively, as was shown by ESI-MS. (NH(4))(1.5)K(3){[Mo(3)Se(7)(CN)(6)]I}I(1.5).4.5H(2)O (4) was isolated and structurally characterized. Reactions of W(3)Q(7)Br(4) (Q = S, Se) with KNCSe lead to [W(3)Q(4)(CN)(9)](5-). Heating W(3)Te(7)Br(4) in KCNSe melt gives a complicated mixture of W(3)Q(7) and W(3)Q(4) derivatives, as was shown by ESI-MS, from which E(3)[W(3)(mu(3)-Te)(mu-TeSe)(3)(CN)(6)]Br.6H(2)O (5) and K(5)[W(3)(mu(3)-Te)(mu-Se)(3)(CN)(9)] (6) were isolated. X-ray analysis of 5 reveals the presence of a new TeSe(2-) ligand. The complexes were characterized by IR, Raman, electronic, and (77)Se and (125)Te NMR spectra and by ESI mass spectrometry.
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http://dx.doi.org/10.1021/ic050962cDOI Listing
October 2005