76
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Sharma R, Pandey AK, Singh Y, Mishra BP, Singh PK, Singh G. Estimation of genetic diversity in Siri cattle from India. RUSS J GENET+ 2009. [DOI: 10.1134/s1022795408110124] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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77
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Khadgawat R, Singh Y, Kansara S, Tandon N, Bal C, Seith A, Kotwal P. PET/CT localisation of a scapular haemangiopericytoma with tumour-induced osteomalacia. Singapore Med J 2009; 50:e55-e57. [PMID: 19296011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Oncogenic osteomalacia, or tumour-induced osteomalacia (TIO), is a rare paraneoplastic syndrome characterised by hypophosphataemia, phosphaturia, inappropriately low serum levels of 1,25-dihydroxyvitamin D for hypophosphataemia. TIO is caused by mesenchymal tumours that secrete phosphaturic substances, leading to increased renal wasting of phosphates. These tumours are very small in size and grow slowly. Localisation of these tumours has always been difficult with the available biochemical and imaging techniques. At times, despite all efforts, the tumour could not be localised. We report our experience with a 42-year-old woman with TIO where whole-body magnetic resonance imaging could not localise the tumour, a scapular haemangiopericytoma. PET/CT was helpful in the localisation of the tumour which, when surgically removed, resulted in the normalisation of biochemical parameters with clinical improvement.
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78
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Bhetariya P, Shankar J, Singh Y, Madan T, Varma A, Basir S, Sarma P. Multiplex PCR for Detection of Aspergillus fumigatus, Aspergillus flavus and Aspergillus niger. J Allergy Clin Immunol 2009. [DOI: 10.1016/j.jaci.2008.12.603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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79
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Sharma R, Pandey AK, Singh Y, Prakash B, Mishra BP, Kathiravan P, Singh PK, Singh G. Evaluation of Genetic Variation and Phylogenetic Relationship among North Indian Cattle Breeds. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2009. [DOI: 10.5713/ajas.2009.70047] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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80
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Palombo M, Singh Y, Sinko P. Prodrug and conjugate drug delivery strategies for improving HIV/AIDS therapy. J Drug Deliv Sci Technol 2009; 19:3-14. [DOI: 10.1016/s1773-2247(09)50001-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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81
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Singh Y. Women's Sexual Health by Gilly Andrews and John Studd. Med J Armed Forces India 2009. [DOI: 10.1016/s0377-1237(09)80074-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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82
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Singh Y, Garg D. Determination of Minimal Inhibitory Concentration for Antibiotics against some Mycoplasma mycoides subsp. mycoides (LC type) Strains. Int J Infect Dis 2008. [DOI: 10.1016/j.ijid.2008.05.551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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83
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Sharma R, Pandey AK, Singh Y, Mishra BP, Singh PK, Singh G. Estimation of genetic diversity in Siri cattle from India. GENETIKA 2008; 44:1532-1538. [PMID: 19137737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Siri cattle, a dual purpose breed of India is currently showing declining population trend. Siri animals have been developing through natural selection and show high adaptation to wide range of hilly terrain (altitudes 150-2500 m). The present work evaluated the genetic diversity of 23 FAO recommended microsatellite loci in a sample of 50 animals. The allele and genotype frequencies, heterozygosities and gene diversity were estimated. A total of 141 alleles were detected by the 23 microsatellite markers investigated. Microsatellites were highly polymorphic with mean allelic number 6.13 +/- 1.63 (ranging from 3-10 per locus). The observed heterozygosity in the population varied from 0.26-0.80 with the mean of 0.53 +/- 0.16, indicating substantial genetic variation in this population. Heterozygote deficiency and mutation-drift equilibrium hypothesis were also examined. Population exhibited heterozygote deficit to the tune of 22.1%. Population was found to be in mutation-drift equilibrium. Substantial genetic variability verified in Siri cattle despite its reducing population size suggests that this breed has a rich reservoir of genetic diversity. This fact and its marked environmental adaptation reinforce the importance of its preservation as a pure breed, and/or its use in agricultural exploitation.
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84
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Ghimire B, Khan MI, Bibhusal T, Singh Y, Sayami P. Accuracy of Triple Test Score in The Diagnosis of Palpable Breast Lump. JNMA J Nepal Med Assoc 2008. [DOI: 10.31729/jnma.155] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Breast lump is a very sensitive issue for the patient so a reliable, non invasive and prompt diagnosishelps to lessen the associated anxiety and leads to early definitive treatment. The aim of this studywas to evaluate the acuracy of Triple Test Score (TTS) as a clinical tool for the diagnosis of a palpablebreast lump. This diagnostic test study was carried out in the Department of Surgery of TribhuvanUniversity Teaching Hospital. Of the 117 patients admitted with breast diseases from the breastclinic over thirteen months, 87 had breast lump. Fifty patients underwent Triple Test Score ( physicalexamination, mammography and fine needle aspiration cytology) and were categorized into benign,suspicious and malignant. This was later correlated with the histopathological findings. Nineteenpatients with breast lumps interpreted by TTS as benign correlated with the histopathologicalfindings whereas of 31 malignant lumps, 30 turned out to be malignant and one benign. This givesTTS an over all accuracy of 98% with 100% sensitivity, 95.2% specificity and positive predictive valueof 96.7%. Carcinoma was seen in 29 (58%) cases in the age group of 35 to 70 years. The mean age atdiagnosis of benign and malignant disease was 41.8 and 45.1 years respectively. In conclusion, TTS isan accurate and least invasive diagnostic test based on which definitive treatment can be initiated.Key words : breast lump, carcinoma breast, triple test score
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85
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Ghimire B, Khan MI, Bibhusal T, Singh Y, Sayami P. Accuracy of triple test score in the diagnosis of palpable breast lump. JNMA J Nepal Med Assoc 2008; 47:189-192. [PMID: 19079392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
Breast lump is a very sensitive issue for the patient so a reliable, non invasive and prompt diagnosis helps to lessen the associated anxiety and leads to early definitive treatment. The aim of this study was to evaluate the accuracy of Triple Test Score (TTS) as a clinical tool for the diagnosis of a palpable breast lump. This diagnostic test study was carried out in the Department of Surgery of Tribhuvan University Teaching Hospital. Of the 117 patients admitted with breast diseases from the breast clinic over thirteen months, 87 had breast lump. Fifty patients underwent Triple Test Score ( physical examination, mammography and fine needle aspiration cytology) and were categorized into benign, suspicious and malignant. This was later correlated with the histopathological findings. Nineteen patients with breast lumps interpreted by TTS as benign correlated with the histopathological findings whereas of 31 malignant lumps, 30 turned out to be malignant and one benign. This gives TTS an over all accuracy of 98% with 100% sensitivity, 95.2% specificity and positive predictive value of 96.7%. Carcinoma was seen in 29 (58%) cases in the age group of 35 to 70 years. The mean age at diagnosis of benign and malignant disease was 41.8 and 45.1 years respectively. In conclusion, TTS is an accurate and least invasive diagnostic test based on which definitive treatment can be initiated.
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86
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Saigal R, Mittal M, Kansal A, Singh Y, Ram H. Comparison of MRI and X-ray in detection of erosions in RA. INDIAN JOURNAL OF RHEUMATOLOGY 2008. [DOI: 10.1016/s0973-3698(10)60126-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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87
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Prasanna R, Jaiswal P, Singh Y, Singh P. Influence of biofertilizers and organic amendments on nitrogenase activity and phototrophic biomass of soil under wheat. ACTA ACUST UNITED AC 2008. [DOI: 10.1556/aagr.56.2008.2.4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The role of blue green algal (BGA) biofertilizers has been limited to its relevance and utilization in rice crops, and scanty information is available on their use in conjunction with organic amendments and their influence on wheat
(Triticum aestivum)
. An experiment was conducted from November 2003 to April 2004 in the fields of the Indian Agricultural Research Institute (IARI), New Delhi, India to evaluate the effect of vermicompost, farmyard manure and biofertilizers (BGA and
Azotobacter
) in different combinations with chemical fertilizers (N
40
P
30
K
30
) in wheat (var. HD 2687). Selected soil biological parameters (cyanobacterial diversity/abundance, nitrogenase activity and the phototrophic biomass of soil cores) were measured. The application of vermicompost in combination with BGA biofertilizer (B+V+N
40
P
30
K
30
) brought about a significant increase in nitrogenase activity (from 0.1 in N
80
P
30
K
30
to 2.0 nmoles mg chl
−1
h
−1
), while
Azotobacter
+ BGA (+N
40
P
30
K
30
) treatment gave the highest values of chlorophyll (1.19 μg g
−1
soil). The addition of vermicompost and farmyard manure (+N
40
P
30
K
30
) enhanced cyanobacterial abundance, and cyanobacterial genera such as
Nostoc, Anabaena, Calothrix, Oscillatoria
and
Phormidium
were the dominant forms observed under the wheat crop. The synergistic effect of organic amendments, biofertilizers and chemical fertilizers, especially BGA inoculants, advocates their utilization in wheat crops to improve soil fertility.
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88
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Khandelwal S, Demonty I, Jeemon P, Lakshmy R, Mukherjee R, Gupta R, Snehi U, Niveditha D, Singh Y, Passi S, Prabhakaran D, Reddy K. PLANT STEROLS, FISH OIL OMEGA-3S, AND THEIR COMBINATION IMPROVE THE PLASMA LIPID PROFILE IN MILDLY HYPERLIPIDEMIC INDIAN ADULTS. ATHEROSCLEROSIS SUPP 2008. [DOI: 10.1016/s1567-5688(08)70551-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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89
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Thapa B, Singh Y, Sayami P, Khanal U. Mammographic diagnosis of breast carcinoma: an institutional experience. JNMA J Nepal Med Assoc 2008; 47:62-65. [PMID: 18709033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Abstract
Mammogram is a common diagnostic modality for breast carcinoma. Diagnostic mammogram is available at only few centers in Nepal. The aim of this study was to determine the accuracy of diagnostic mammogram in Nepalese women suffering from breast carcinoma. A retrospective analysis of the breast carcinoma was carried out in the Department of Surgery, Tribhuwan University Teaching Hospital from October 1995 to October 2007. Out of 556 patients with histologically proven breast carcinoma, 378 patients (68%) had undergone mammography. Breast carcinoma was identified on mammography in 328 (87%) cases while 50 cases (13%) were reported as normal or benign lesions. Diagnostic mammogram had a sensitivity of 86.8%, a specificity of 98.6% with a positive predictive value of 68.8% and a negative predictive value of 99.5%. In mammographically missed breast carcinoma, 34% were less than 40 years of age (P<0.05), 60% were premenopausal (P<0.05) and 88% patients presented with a painless lump. The study shows that the diagnostic accuracy of the mammogram is very high. However, there is a chance of missing the breast carcinoma in young and premenopausal women.
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90
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Sidharth D, Thapa B, Singh Y, Sayami P, Khanal U. Mammographic Diagnosis of Breast Carcinoma: An Institutional Experience. JNMA J Nepal Med Assoc 2008. [DOI: 10.31729/jnma.312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Mammogram is a common diagnostic modality for breast carcinoma. Diagnostic mammogramis available at only few centers in Nepal. The aim of this study was to determine the accuracy ofdiagnostic mammogram in Nepalese women suffering from breast carcinoma. A retrospectiveanalysisofthebreast carcinomawas carriedoutintheDepartmentof Surgery,TribhuwanUniversityTeaching Hospital from October 1995 to October 2007. Out of 556 patients with histologically proven breast carcinoma, 378 patients (68%) had undergone mammography. Breast carcinoma was identified on mammography in 328 (87%) cases while 50 cases (13%) were reported as normal or benign lesions. Diagnostic mammogram had a sensitivity of 86.8%, a specificity of 98.6% with a positive predictive value of 68.8% and a negative predictive value of 99.5%. In mammographically missed breast carcinoma, 34% were less than 40 years of age (P<0.05), 60% were premenopausal (P<0.05) and 88% patients presented with a painless lump. The study shows that the diagnostic accuracy of the mammogram is very high. However, there is a chance of missing the breast carcinoma in youngand premenopausal women.Key words: breast carcinoma, diagnostic mammogram, premenopausal women
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91
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Singh Y, Shankar A, Dutta S, Chari V. Adnexal Torsion in Second Trimester of Pregnancy. Med J Armed Forces India 2008; 64:193-4. [PMID: 27408137 DOI: 10.1016/s0377-1237(08)80084-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2007] [Accepted: 08/25/2007] [Indexed: 11/30/2022] Open
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92
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Saigal R, Mittal M, Kansal A, Singh Y, Kolar PR, Jain S. Fat embolism syndrome. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 2008; 56:245-249. [PMID: 18702388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Fat embolism syndrome is a rare complication occurring in 0.5 to 2% of patients following a long bone fracture. It is believed to be caused by the toxic effects of free fatty acids. Diagnosis is clinical, based on respiratory, cerebral and dermal manifestations. Treatment is only supportive, directed mainly at maintaining respiratory functions.
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93
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Spinelli N, Singh Y, Defrancq E, Dumy P. Aldehydic oligonucleotide: a key intermediate for the preparation of oligonucleotide conjugates through oxime bond formation. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2008; 26:883-7. [PMID: 18058501 DOI: 10.1080/15257770701505436] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Oligonucleotides functionalized with an aldehyde group are the key intermediates used for the preparation of peptide-oligonucleotide conjugates through the formation of an oxime linkage. Herein, we describe a brief overview of various synthetic protocols developed in our laboratory for the preparation of aldehyde containing oligonucleotides and their subsequent conjugation with peptides.
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94
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Saigal R, Mittal M, Kansal A, Singh Y, Ram H. Inflammatory Myopathy During Etanercept Therapy in a Patient with Rheumatoid Arthritis. INDIAN JOURNAL OF RHEUMATOLOGY 2008. [DOI: 10.1016/s0973-3698(10)60085-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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95
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Defrancq E, Singh Y, Spinelli N. Chemical Strategies for Oligonucleotide-Conjugates Synthesis. CURR ORG CHEM 2008. [DOI: 10.2174/138527208783743732] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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96
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Singh Y, Chari VRR, Basu SK, Ratnam A. Cornual Rupture of Uterus. Med J Armed Forces India 2008; 64:81. [PMID: 27408091 PMCID: PMC4921748 DOI: 10.1016/s0377-1237(08)80161-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Accepted: 04/11/2007] [Indexed: 11/22/2022] Open
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97
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Harrison RS, Sharpe PC, Singh Y, Fairlie DP. Amyloid peptides and proteins in review. Rev Physiol Biochem Pharmacol 2007; 159:1-77. [PMID: 17846922 DOI: 10.1007/112_2007_0701] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Amyloids are filamentous protein deposits ranging in size from nanometres to microns and composed of aggregated peptide beta-sheets formed from parallel or anti-parallel alignments of peptide beta-strands. Amyloid-forming proteins have attracted a great deal of recent attention because of their association with over 30 diseases, notably neurodegenerative conditions like Alzheimer's, Huntington's, Parkinson's, Creutzfeldt-Jacob and prion disorders, but also systemic diseases such as amyotrophic lateral sclerosis (Lou Gehrig's disease) and type II diabetes. These diseases are all thought to involve important conformational changes in proteins, sometimes termed misfolding, that usually produce beta-sheet structures with a strong tendency to aggregate into water-insoluble fibrous polymers. Reasons for such conformational changes in vivo are still unclear. Intermediate aggregated state(s), rather than precipitated insoluble polymeric aggregates, have recently been implicated in cellular toxicity and may be the source of aberrant pathology in amyloid diseases. Numerous in vitro studies of short and medium length peptides that form amyloids have provided some clues to amyloid formation, with an alpha-helix to beta-sheet folding transition sometimes implicated as an intermediary step leading to amyloid formation. More recently, quite a few non-pathological amyloidogenic proteins have also been identified and physiological properties have been ascribed, challenging previous implications that amyloids were always disease causing. This article summarises a great deal of current knowledge on the occurrence, structure, folding pathways, chemistry and biology associated with amyloidogenic peptides and proteins and highlights some key factors that have been found to influence amyloidogenesis.
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98
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Lignier H, Sias C, Ciampini D, Singh Y, Zenesini A, Morsch O, Arimondo E. Dynamical control of matter-wave tunneling in periodic potentials. PHYSICAL REVIEW LETTERS 2007; 99:220403. [PMID: 18233266 DOI: 10.1103/physrevlett.99.220403] [Citation(s) in RCA: 130] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Indexed: 05/25/2023]
Abstract
We report on measurements of dynamical suppression of interwell tunneling of a Bose-Einstein condensate (BEC) in a strongly driven optical lattice. The strong driving is a sinusoidal shaking of the lattice corresponding to a time-varying linear potential, and the tunneling is measured by letting the BEC freely expand in the lattice. The measured tunneling rate is reduced and, for certain values of the shaking parameter, completely suppressed. Our results are in excellent agreement with theoretical predictions. Furthermore, we have verified that, in general, the strong shaking does not destroy the phase coherence of the BEC, opening up the possibility of realizing quantum phase transitions by using the shaking strength as the control parameter.
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99
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Swami A, Kurupati RK, Pathak A, Singh Y, Kumar P, Gupta KC. A unique and highly efficient non-viral DNA/siRNA delivery system based on PEI-bisepoxide nanoparticles. Biochem Biophys Res Commun 2007; 362:835-41. [PMID: 17822674 DOI: 10.1016/j.bbrc.2007.08.073] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2007] [Accepted: 08/13/2007] [Indexed: 11/24/2022]
Abstract
Delivery of DNA and siRNA into mammalian cells is a powerful technique in treating various diseases caused by single gene defects. Herein, we report a highly efficient delivery system using 1,4-butanediol diglycidyl ether (bisepoxide) crosslinked polyethylenimine (PEI) nanoparticles (PN). The nanoparticle/DNA complexes (nanoplexes) exibited approximately 2.5- to 5.0-fold gene transfer efficacy and decreased cytotoxicity in cultured cell lines, compared to the native PEI (25 kDa) (gold standard) and commercially available transfection agents such as Lipofectamine 2000 and Fugene. The bisepoxide crosslinking results in change in amine ratio in PEI; however, it retains the net charge on PN unaltered. A series of nanoparticles obtained by varying the degree of crosslinking was found to be in the size range of 69-77 nm and the zeta potential varying from +35 to 40 mV. The proposed system was also found to deliver siRNA efficiently into HEK cells, resulting in approximately 70% suppression of the targetted gene (GFP).
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100
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Swami A, Aggarwal A, Pathak A, Patnaik S, Kumar P, Singh Y, Gupta KC. RETRACTED: Imidazolyl-PEI modified nanoparticles for enhanced gene delivery. Int J Pharm 2007; 335:180-192. [PMID: 17169517 DOI: 10.1016/j.ijpharm.2006.11.033] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2006] [Revised: 11/01/2006] [Accepted: 11/03/2006] [Indexed: 10/23/2022]
Abstract
The derivatives of polyethylenimine (PEI 25 and 750kDa) were synthesized by partially substituting their amino groups with imidazolyl moieties. The series of imidazolyl-PEIs thus obtained were cross-linked with polyethylene glycol (PEG) to get imidazolyl-PEI-PEG nanoparticles (IPP). The component of hydrophobicity was introduced by grafting the lauryl groups in the maximal substituted IPP nanoparticles (IPPL). The nanoparticles were characterized with respect to DNA interaction, hydrodynamic diameter, zeta potential, in vitro cytotoxicity and transfection efficiency on model cell lines. The IPP and IPPL nanoparticles formed a loose complex with DNA compared to the corresponding native PEI, leading to more efficient unpackaging of DNA. The DNA loading capacity of IPP and IPPL nanoparticles was also lower compared to PEI. The imidazolyl substitution improved the gene delivery efficiency of PEI (750kDa) by nine- to ten-fold and PEI (25kDa) by three- to four-fold. At maximum transfection efficiency, the zeta potential of nanoparticles was positive after forming a complex with DNA. The maximum level of reporter gene expression was mediated by IPPL nanoparticles in both the series. The cytotoxicity, another pertinent problem with cationic polymers, was also negligible in case of IPP and IPPL nanoparticles.
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