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Joshi PR, Tsuge M, Tseng CY, Lee YP. Infrared spectra of isoquinolinium (iso-C 9H 7NH +) and isoquinolinyl radicals (iso-C 9H 7NH and 1-, 3-, 4-, 5-, 6-, 7- and 8-iso-HC 9H 7N) isolated in solid para-hydrogen. Phys Chem Chem Phys 2023; 25:11934-11950. [PMID: 36916330 DOI: 10.1039/d3cp00246b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Protonated polycyclic aromatic nitrogen heterocycles (H+PANH) are prospective candidates that may contribute to interstellar unidentified infrared (UIR) emission bands because protonation enhances the relative intensities of the bands near 6.2, 7.7 and 8.6 μm, and the presence of the N atom induces a blue shift of the ring-stretching modes so that the spectra of H+PANH match better with the 6.2 μm feature in class-A UIR spectra. We report the infrared (IR) spectra of protonated isoquinoline (the 2-isoquinolinium cation, iso-C9H7NH+), its neutral counterpart (the 2-isoquinolinyl radical, iso-C9H7NH), and another mono-hydrogenated product (the 6-isoquinolinyl radical, 6-iso-HC9H7N), produced on the electron-bombardment of a mixture of isoquinoline (iso-C9H7N) with excess para-hydrogen (p-H2) during matrix deposition at 3.2 K. To generate additional isomers of hydrogenated isoquinoline, we irradiated iso-C9H7N/Cl2/p-H2 matrices at 365 nm to generate Cl atoms, followed by IR irradiation to generate H atoms via Cl + H2 (v = 1) → HCl + H; the H atoms thus generated reacted with iso-C9H7N. In addition to iso-C9H7NH and 6-iso-HC9H7N observed in the electron-bombardment experiments, we identified six additional hydrogenated isoquinoline species, 1-, 3-, 4-, 5-, 7- and 8-iso-HC9H7N, via their IR spectra; hydrogenation on the N atom and all available carbon atoms except for the two sharing carbon atoms on the fused ring was observed. Spectral groupings were achieved according to their behaviors after maintenance of the matrix in darkness and on secondary photolysis at various wavelengths. The assignments were supported via comparison of the experimental results with the vibrational wavenumbers and IR intensities of possible isomers predicted using the B3LYP/6-311++G(d,p) method. The implications in the identification of the UIR band are discussed.
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Affiliation(s)
- Prasad Ramesh Joshi
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
| | - Masashi Tsuge
- Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, Japan.
| | - Chih-Yu Tseng
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
| | - Yuan-Pern Lee
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan. .,Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan.
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2
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Tsai HR, Joshi PR, Witek HA, Lee YP. Spectral Evidence of Bevel-Gear-Type Rotation of Benzene around Br in Solid p-H 2: Infrared Spectrum of the C 6H 6Br Radical. J Phys Chem Lett 2023; 14:460-467. [PMID: 36622967 DOI: 10.1021/acs.jpclett.2c03262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Whether the structure of C6H6X (X = halogen), an intermediate in the halogenation of benzene, is an open or a bridged form has been debated. We produced Br to react with C6H6 upon photolysis in situ of a Br2/C6H6/p-H2 matrix at 3.2 K. In contrast to the C6H6Cl σ-complex reported previously, the observed infrared spectrum indicates that C6H6Br is an open-form π-complex. Furthermore, lines of the two CH out-of-plane bending modes associated mainly with even- and odd-numbered carbons, predicted near 672 and 719 cm-1, merged into a broad line at 697.3 cm-1, indicating that these modes become nearly equivalent as Br migrates from one carbon atom to another. Quantum-chemical calculations support that the benzene ring performs a bevel-gear-type rotation with respect to Br. Observation of only trans-ortho- and trans-para-C6H6Br2 suggests that this gear-type motion allows the additional Br atom to attack C6H6Br only from the opposite side of the Br atom in C6H6Br.
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Affiliation(s)
- Huei-Ru Tsai
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan
| | - Prasad Ramesh Joshi
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan
| | - Henryk A Witek
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan
- Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan
| | - Yuan-Pern Lee
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan
- Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan
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Haupa KA, Joshi PR, Lee Y. Hydrogen‐atom tunneling reactions in solid
para
‐hydrogen and their applications to astrochemistry. J CHIN CHEM SOC-TAIP 2022. [DOI: 10.1002/jccs.202200210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Karolina Anna Haupa
- Department of Applied Chemistry and Institute of Molecular Science National Yang Ming Chiao Tung University Hsinchu Taiwan
- Institute of Physical Chemistry Karlsruhe Institute of Technology Karlsruhe Germany
| | - Prasad Ramesh Joshi
- Department of Applied Chemistry and Institute of Molecular Science National Yang Ming Chiao Tung University Hsinchu Taiwan
| | - Yuan‐Pern Lee
- Department of Applied Chemistry and Institute of Molecular Science National Yang Ming Chiao Tung University Hsinchu Taiwan
- Center for Emergent Functional Matter Science National Yang Ming Chiao Tung University Hsinchu Taiwan
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Joshi PR, Lee YP. A chemical link between methylamine and methylene imine and implications for interstellar glycine formation. Commun Chem 2022; 5:62. [PMID: 36697745 PMCID: PMC9814145 DOI: 10.1038/s42004-022-00677-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 04/26/2022] [Indexed: 01/28/2023] Open
Abstract
Methylamine CH3NH2 is considered to be an important precursor of interstellar amino acid because hydrogen abstraction might lead to the aminomethyl radical •CH2NH2 that can react with •HOCO to form glycine, but direct evidence of the formation and spectral identification of •CH2NH2 remains unreported. We performed the reaction H + CH3NH2 in solid p-H2 at 3.2 K and observed IR spectra of •CH2NH2 and CH2NH upon irradiation and when the matrix was maintained in darkness. Previously unidentified IR spectrum of •CH2NH2 clearly indicates that •CH2NH2 can be formed from the reaction H + CH3NH2 in dark interstellar clouds. The observed dual-cycle mechanism containing two consecutive H-abstraction and two H-addition steps chemically connects CH3NH2 and CH2NH in interstellar media and explains their quasi-equilibrium. Experiments on CD3NH2 produced CD2HNH2, in addition to •CD2NH2 and CD2NH, confirming the occurrence of H addition to •CD2NH2.
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Affiliation(s)
- Prasad Ramesh Joshi
- grid.260539.b0000 0001 2059 7017Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu, Taiwan
| | - Yuan-Pern Lee
- grid.260539.b0000 0001 2059 7017Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu, Taiwan ,grid.260539.b0000 0001 2059 7017Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu, Taiwan ,grid.28665.3f0000 0001 2287 1366Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan
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Schneiker A, Góbi S, Joshi PR, Bazsó G, Lee YP, Tarczay G. Non-energetic, Low-Temperature Formation of C α-Glycyl Radical, a Potential Interstellar Precursor of Natural Amino Acids. J Phys Chem Lett 2021; 12:6744-6751. [PMID: 34264091 DOI: 10.1021/acs.jpclett.1c01306] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The reaction of H atoms with glycine was investigated at 3.1 K in para-H2, a quantum-solid host. The reaction was followed by IR spectroscopy, with the spectral analysis aided by quantum chemical computations. Comparison of the experimental IR spectrum with computed anharmonic frequencies and intensities proved that, regardless of the reactant glycine conformation, Cα-glycyl radical is formed in an H-atom-abstraction process with great selectivity. The product of the second H-atom abstraction, iminoacetic acid, was also observed in a smaller amount. The Cα-glycyl radical is sensitive to UV light and decomposes to iminoacetic acid and H atom upon 280 nm radiation. Since the reactive radical center is located on the Cα-atom, it is suggested that natural α-amino acids can be formed from glycine via the Cα-glycyl radical by non-energetic mechanisms in the solid phase of the interstellar medium.
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Affiliation(s)
- Anita Schneiker
- MTA-ELTE Lendület Laboratory Astrochemistry Research Group, Institute of Chemistry, ELTE Eötvös Loránd University, H-1518 Budapest, Hungary
- Laboratory of Molecular Spectroscopy, Institute of Chemistry, ELTE Eötvös Loránd University, H-1518 Budapest, Hungary
| | - Sándor Góbi
- MTA-ELTE Lendület Laboratory Astrochemistry Research Group, Institute of Chemistry, ELTE Eötvös Loránd University, H-1518 Budapest, Hungary
| | - Prasad Ramesh Joshi
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan
| | - Gábor Bazsó
- Wigner Research Centre for Physics, P. O. Box 49, H-1525 Budapest, Hungary
| | - Yuan-Pern Lee
- Department of Applied Chemistry and Institute of Molecular Science, National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan
- Center for Emergent Functional Matter Science, National Chiao Tung University, Hsinchu 300093, Taiwan
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106319, Taiwan
| | - György Tarczay
- MTA-ELTE Lendület Laboratory Astrochemistry Research Group, Institute of Chemistry, ELTE Eötvös Loránd University, H-1518 Budapest, Hungary
- Laboratory of Molecular Spectroscopy, Institute of Chemistry, ELTE Eötvös Loránd University, H-1518 Budapest, Hungary
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6
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Joshi PR, Sankaran K. P⋯N type pnicogen bonding in phosphorus trichloride–pyridine adduct: A matrix isolation infrared, DFT and ab initio study. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.128408] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Singh SK, Joshi PR, Shaw RA, Hill JG, Das A. Interplay between hydrogen bonding and n→π* interaction in an analgesic drug salicin. Phys Chem Chem Phys 2018; 20:18361-18373. [PMID: 29942975 DOI: 10.1039/c8cp00655e] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The competition and cooperation between weak intermolecular interactions are important in determining the conformational preferences of molecules. Understanding the relative strengths of these effects in the context of potential drug candidates is therefore essential. We use a combination of gas-phase spectroscopy and quantum-chemical calculations to elucidate the nature of such interactions for the analgesic salicin [2-(hydroxymethyl)phenyl β-d-glucopyranoside], an analog of aspirin found in willow bark. Of several possible conformers, only three are observed experimentally, and these are found to correspond with the three lowest energy conformers obtained from density functional theory calculations and simulated Franck-Condon spectra. Natural bond orbital analyses show that these are characterized by a subtle interplay between weak n→π* interaction and conventional strong hydrogen bond, with additional insights into this interaction provided by analysis of quantum theory of atoms in molecules and symmetry-adapted perturbation theory calculations. In contrast, the higher energy conformers, which are not observed experimentally, are mostly stabilized by the hydrogen bond with negligible contribution of n→π* interaction. The n→π* interaction results in a preference for the benzyl alcohol group of salicin to adopt a gauche conformation, a characteristic also found when salicin is bound to the β-glucosidase enzyme. As such, understanding the interplay between these weak interactions has significance in the rationalization of protein structures.
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Affiliation(s)
- Santosh K Singh
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune-411008, Maharashtra, India.
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8
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Joshi PR, Ramanathan N, Sundararajan K, Sankaran K. Evidence for Phosphorus Bonding in Phosphorus Trichloride–Methanol Adduct: A Matrix Isolation Infrared and ab Initio Computational Study. J Phys Chem A 2015; 119:3440-51. [DOI: 10.1021/jp511156d] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Prasad Ramesh Joshi
- Chemistry
Group, Indira Gandhi Center for Atomic Research, Kalpakkam 603102, Tamil Nadu, India
| | - N. Ramanathan
- Chemistry
Group, Indira Gandhi Center for Atomic Research, Kalpakkam 603102, Tamil Nadu, India
| | - K. Sundararajan
- Chemistry
Group, Indira Gandhi Center for Atomic Research, Kalpakkam 603102, Tamil Nadu, India
| | - K. Sankaran
- Chemistry
Group, Indira Gandhi Center for Atomic Research, Kalpakkam 603102, Tamil Nadu, India
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9
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Affiliation(s)
- Emilie-Laure Zins
- UPMC Univ. Paris 06, UMR 7075, Laboratoire de Dynamique, Interactions, et Réactivité (LADIR), F-75005, Paris, France
- CNRS, UMR 7075, Laboratoire de Dynamique, Interactions et Réactivité (LADIR), F-75005, Paris, France
| | - Claire Pirim
- UPMC Univ. Paris 06, UMR 7075, Laboratoire de Dynamique, Interactions, et Réactivité (LADIR), F-75005, Paris, France
- CNRS, UMR 7075, Laboratoire de Dynamique, Interactions et Réactivité (LADIR), F-75005, Paris, France
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332,
United States
| | - Prasad Ramesh Joshi
- UPMC Univ. Paris 06, UMR 7075, Laboratoire de Dynamique, Interactions, et Réactivité (LADIR), F-75005, Paris, France
- CNRS, UMR 7075, Laboratoire de Dynamique, Interactions et Réactivité (LADIR), F-75005, Paris, France
| | - Lahouari Krim
- UPMC Univ. Paris 06, UMR 7075, Laboratoire de Dynamique, Interactions, et Réactivité (LADIR), F-75005, Paris, France
- CNRS, UMR 7075, Laboratoire de Dynamique, Interactions et Réactivité (LADIR), F-75005, Paris, France
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10
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Pandey RA, Joshi PR, Mudliar SN, Deshmukh SC. Biological treatment of waste gas containing mixture of monochlorobenzene (MCB) and benzene in a bench scale biofilter. Bioresour Technol 2010; 101:5168-5174. [PMID: 20202831 DOI: 10.1016/j.biortech.2010.02.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 01/30/2010] [Accepted: 02/03/2010] [Indexed: 05/28/2023]
Abstract
The paper outlines treatment of waste gas containing monochlorobenzene (MCB) and benzene in a mixture using biofilter packed with compost and woodchips seeded with Acinetobacter calcoaceticus. The biofilter could treat waste gas containing MCB and benzene effectively with an efficiency of (99+/-5%) and (97+/-6%) at optimal empty bed contact time (EBCT) of 3 min with a loading of 57 g/m(3)/h of MCB and 2g/m(3)/h of benzene. At optimum loading of MCB and benzene, the biofilter showed total bacterial count of 13 x 10(5)CFU/g of compost, while the MCB and benzene degrading bacterial count was 71 x 10(4)CFU/g and 5 x 10(4)CFU/g compost respectively. The experimental removal efficiency of MCB and benzene were in good agreement with the model predicted value.
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Affiliation(s)
- R A Pandey
- National Environmental Engineering Research Institute, Nehru Marg, Nagpur 440020, India.
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11
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Joshi PR, Gläser D, Schmidt S, Vorgerd M, Winterholler M, Eger K, Zierz S, Deschauer M. Molecular diagnosis of German patients with late-onset glycogen storage disease type II. J Inherit Metab Dis 2008; 31 Suppl 2:S261-5. [PMID: 18607768 DOI: 10.1007/s10545-008-0820-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2007] [Revised: 02/11/2008] [Accepted: 04/22/2008] [Indexed: 11/24/2022]
Abstract
UNLABELLED In patients with late-onset glycogen storage disease type II, one mutation, c.-32-13T>G, in the α-glucosidase (GAA) gene is identified frequently in European populations from different regions along with many rarer mutations. We have performed molecular genetic investigations in 18 German index patients with late-onset disease. The c.-32-13T>G, c.525delT (p.Glu176fsX45), and c.2481+102_2646+31del mutations were detected by PCR/restriction enzyme digest. Other mutations were detected by sequencing. All patients were compound heterozygous and 17 patients harboured the c.-32-13T>G mutation. Seven other previously described mutations (including the c.-32-13T>G) were identified, of which the p.C103G (c.307T>G) and the c.2481+102_2646+31del mutations were present each in three unrelated patients. Sequencing revealed five novel mutations. CONCLUSIONS Genetic testing was able to identify the genetic defects in all patients and screening of the c.-32-13T>G mutation identified 94% of the cases. This is important for quick and reliable diagnosis, especially in view of enzyme replacement. Among the rarer mutations, c.2481+102_2646+31del and p.C103G are rather frequent in Germany.
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Affiliation(s)
- P R Joshi
- Neurologische Universitätsklinik, Halle, Germany.
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12
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Joshi PR, Bhat GS, Dixit S. Selection of articulator for general dental practice. Kathmandu Univ Med J (KUMJ) 2008; 6:112-116. [PMID: 18604127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Affiliation(s)
- P R Joshi
- Department of Prosthodontics and Maxillofacial Prosthetics, Manipal college of Dental Science, Mangalore, Karnataka, India
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13
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Deschauer M, Morgenroth A, Joshi PR, Gläser D, Chinnery PF, Aasly J, Schreiber H, Knape M, Zierz S, Vorgerd M. Analysis of spectrum and frequencies of mutations in McArdle disease. Identification of 13 novel mutations. J Neurol 2007; 254:797-802. [PMID: 17404776 DOI: 10.1007/s00415-006-0447-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2006] [Revised: 10/02/2006] [Accepted: 10/19/2006] [Indexed: 10/23/2022]
Abstract
BACKGROUND McArdle disease, a common metabolic myopathy with autosomal recessive inheritance, is caused by a frequent R50X mutation and many rare mutations in the myophosphorylase gene. OBJECTIVES To identify spectrum and frequencies of myophosphorylase gene mutations in a large cohort of patients with McArdle disease, to discuss diagnostic implications, and to analyse genotype-phenotype relationship. METHODS Molecular genetic analysis of 56 index patients with muscle biopsy-proven myophosphorylase deficiency from Germany (n = 35), UK (n = 13), and several other countries (n = 8) was performed using direct sequencing. RESULTS Allele frequency of the R50X mutation was 58%, and 71% of the patients carried this mutation at least on one allele. We detected 26 other less common mutations, 13 of which are novel: G157V, R161C, Q337R, E384K, S450L, G486D, R570W, K575E, IVS6-2A>T, IVS10+1G>A, R650X, c.1354insC, c.1155_1156delGG. There was no genotype-phenotype correlation with respect to age of onset and severity. R270X was the most frequent mutation among the less common mutations reaching an allele frequency of 5% followed by R94W and G686R representing a frequency of 4% each. CONCLUSIONS The study further extends the genetic heterogeneity of myophosphorylase gene mutations showing no mutational hotspot and no genotype-phenotype correlation. Most novel missense mutations were located in secondary structures or active sites of the enzyme. Some of the less common mutations are recurrent with different frequencies within Europe. Ethnic origin and frequency of less common mutations must be considered to establish efficient strategies in molecular genetic testing. Performing molecular testing can avoid muscle biopsy.
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Affiliation(s)
- M Deschauer
- Klinik und Poliklinik für Neurologie, Martin-Luther Universität Halle-Wittenberg, Ernst-Grube-Str. 40, 06097 Halle/Saale, Germany.
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Shrestha UK, Koirala B, Shrestha BMS, Shrestha R, Joshi PR, Marhatta MN. Clinical Manifestations in Atrial Myxoma. JNMA J Nepal Med Assoc 2004. [DOI: 10.31729/jnma.580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
In Nepal, we started regular open-heart surgery since February 1997. Primary tumors of the heart are rareand the commonest is myxoma. Left atrium is the commonest site of occurrence. There is diagnostic difficultyin this most frequent benign tumor of the heart.We present 5 cases of left atrial myxomas who presented with different clinical features. Among them 4cases were diagnosed preoperatively by transthoracic echocardiography.The youngest was 32 years whereas the oldest was 58 years (mean 49.8 years) and 4 of them were female.Among them, one presented with right unilobar pulmonary venous hypertension; another mimicking mitralstenosis with large left atrial clot; with embolization to brain with motor the third aphasia and the remainingtwo had only constitutional symptoms. All of them were discharged with successful removal of tumor andare surviving at present with no features of recurrence.There are no pathognomic features of atrial myxoma. All suspected cases must be subjected forechocardiography. With the advent of open-heart surgery, extirpation of tumors with good outcome hasbeen a regular service in our hospital.Key Words: Atrial myxoma, Transthoracic Echocardiography, Embolization, Recurrence.
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Abstract
Xenopus laevis oocytes are used extensively in the study of ion channel coupled receptors. Efficient use of oocytes for ion channel characterization requires a system that is inherently stable, reproducible, minimizes drug volumes, and maximizes oocyte longevity. We have constructed a vertical flow oocyte recording chamber to address the aforesaid issues, where the oocyte is placed in a funnel-shaped chamber and perfused from the bottom of the funnel. The vertical rather than horizontal flow of perfusate results in an unusually stable environment for oocyte recording. Two-electrode voltage clamp recordings from a single oocyte are acquired easily and routinely over several hours while maintaining stable baseline currents and reproducible response profiles. Chamber characteristics were tested using a serotonin ligand-gated ion channel receptor (5-HT3R). Data obtained from this system corresponds well with published data. To further test the stability and reliability of this perfusion chamber, we constructed an automated oocyte perfusion system utilizing a commonly available HPLC autosampler. We were able to obtain dose-response curves for various 5-HT3AR ligands using the automated perfusion system with minimal user intervention. Such a system can easily satisfy need for automated oocyte electrophysiology in academic settings, especially small to medium sized laboratories.
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MESH Headings
- Animals
- Automation/instrumentation
- Automation/methods
- Computer-Aided Design
- Diffusion Chambers, Culture/instrumentation
- Diffusion Chambers, Culture/methods
- Dose-Response Relationship, Drug
- Drug Evaluation, Preclinical/methods
- Electric Conductivity
- Electrophysiology
- Female
- Humans
- Membrane Potentials/drug effects
- Membrane Potentials/physiology
- Microinjections/methods
- Oocytes/drug effects
- Oocytes/physiology
- Patch-Clamp Techniques
- Perfusion/methods
- RNA, Complementary/biosynthesis
- Receptors, Serotonin, 5-HT3/drug effects
- Receptors, Serotonin, 5-HT3/genetics
- Receptors, Serotonin, 5-HT3/metabolism
- Serotonin/pharmacology
- Xenopus laevis
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Affiliation(s)
- P R Joshi
- School of Pharmacy, The University of Louisiana at Monroe, Monroe, LA 71209, USA
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16
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Ichhpujani RL, Grover SS, Joshi PR, Kumari S, Verghese T. Prevalence of diphtheria and tetanus antibodies in young adults in Delhi. J Commun Dis 1993; 25:27-9. [PMID: 8014436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A total of 574 blood samples collected mainly from adult males, on a random basis, were tested for diphtheria and tetanus antibodies by Indirect Haemagglutination (IHA) test to find out the percentage of individuals with protective titres (> or = 0.015 IU/ml). A total of 502 (87.5 per cent) and 437 (76.2 per cent) of these had protective titres against diphtheria and tetanus respectively. The vaccination status of these subjects against diphtheria and tetanus was not ascertainable. The relevance of these findings is discussed.
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Ichhpujani RL, Mohan R, Grover SS, Joshi PR, Kumari S. Nasopharyngeal carriage of Neisseria meningitidis in general population and meningococcal disease. J Commun Dis 1990; 22:264-8. [PMID: 2129123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Nasopharyngeal carriage of Neisseria meningitidis was determined in the normal healthy population in Delhi at monthly intervals for a period of 2 years from January, 1986 to December, 1987. Of a total of 6513 individuals screened only 107 (1.64 per cent) were found to carry Neisseria meningitidis serogroup A. There was no age and sex difference in carriage. During the same period, data of laboratory confirmed cases of meningitis due to N. meningitidis serogroup A was obtained from 6 hospitals of Delhi which acted as sentinel centres. Of the total 11,870 pyogenic C.S.F. samples processed, only 557 (4.69 per cent) were due to N. meningitidis serogroup A. There was no correlation observed between the nasopharyngeal meningococcal carriage in the healthy population with the disease prevalence. There was no seasonal variation in nasopharyngeal carriage though upsurge in the number of meningococcal meningitis cases was noticed from January to April.
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