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Fisher DZ, Chaudhary N, Blobel G. cDNA sequencing of nuclear lamins A and C reveals primary and secondary structural homology to intermediate filament proteins. Proc Natl Acad Sci U S A 1986; 83:6450-4. [PMID: 3462705 PMCID: PMC386521 DOI: 10.1073/pnas.83.17.6450] [Citation(s) in RCA: 478] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The amino acid sequences deduced from cDNA clones of human lamin A and lamin C show identity between these two lamins except for an extra 9.0-kDa carboxyl-terminal tail that is present only in lamin A. Both lamins A and C contain an alpha-helical domain of approximately 360 residues that shows striking homology to a corresponding alpha-helical rod domain that is the structural hallmark of all intermediate filament proteins. However, the lamin alpha-helical domain is 14% larger than that of the intermediate filament proteins. In addition to the extensive homology to intermediate filament proteins as reported [McKeon, F., Kirschner, M. & Caput, D. (1986) Nature (London) 319, 463-468], a different 82-amino acid residue stretch at the carboxyl terminus of lamin A has been deduced and verified by amino acid sequencing. This region contains sequence homology to amino- and carboxylterminal domains of type I and type II epidermal keratins. Implications of the presence of these and other domains in lamins A and C for the assembly of the nuclear lamina are discussed.
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478 |
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Abstract
The nuclear envelope consists of three distinct membrane domains: the outer membrane with the bound ribosomes, the inner membrane with the bound lamina, and the pore membrane with the bound pore complexes. Using biochemical and morphological methods, we observed that the nuclear membranes of HeLa cells undergoing mitosis are disassembled in a domain-specific manner, i.e., integral membrane proteins representing the inner nuclear membrane (the lamin B receptor) and the nuclear pore membrane (gp210) are segregated into different populations of mitotic vesicles. At the completion of mitosis, the inner nuclear membrane-derived vesicles associate with chromatin first, beginning in anaphase, whereas the pore membranes and the lamina assemble later, during telophase and cytokinesis. Our data suggest that the ordered reassembly of the nuclear envelope is triggered by the early attachment of inner nuclear membrane-derived vesicles to the chromatin.
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research-article |
32 |
174 |
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Moss SF, Krivosheyev V, de Souza A, Chin K, Gaetz HP, Chaudhary N, Worman HJ, Holt PR. Decreased and aberrant nuclear lamin expression in gastrointestinal tract neoplasms. Gut 1999; 45:723-9. [PMID: 10517909 PMCID: PMC1727735 DOI: 10.1136/gut.45.5.723] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
BACKGROUND Altered expression of lamins A/C and B1, constituent proteins of the nuclear lamina, may occur during differentiation and has also been reported in primary lung cancer. AIMS To examine the expression of these proteins in gastrointestinal neoplasms. PATIENTS Archival human paraffin wax blocks and frozen tissue from patients undergoing surgical resection or endoscopic biopsy. METHODS Immunohistochemistry and western blotting using polyclonal antisera against A type lamins and lamin B1. RESULTS The expression of lamin A/C was reduced and was frequently undetectable by immunohistochemistry in all primary colon carcinomas and adenomas, and in 7/8 primary gastric cancers. Lamin B1 expression was reduced in all colon cancers, 16/18 colonic adenomas, and 6/8 gastric cancers. Aberrant, cytoplasmic labelling with both antibodies occurred in some colonic cancers and around one third of colonic adenomas. Cytoplasmic lamin A/C expression was detected in 3/8 gastric cancers. Lamin expression was reduced in gastric dysplasia, but not intestinal metaplasia, atrophy, or chronic gastritis. Lamin expression was low in carcinomas of oesophagus, prostate, breast, and uterus, but not pancreas. CONCLUSIONS Reduced expression of nuclear lamins, sometimes together with aberrant, cytoplasmic immunoreactivity is common in gastrointestinal neoplasms. Altered lamin expression may be a biomarker of malignancy in the gastrointestinal tract.
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26 |
103 |
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Bishop JS, Guy-Caffey JK, Ojwang JO, Smith SR, Hogan ME, Cossum PA, Rando RF, Chaudhary N. Intramolecular G-quartet motifs confer nuclease resistance to a potent anti-HIV oligonucleotide. J Biol Chem 1996; 271:5698-703. [PMID: 8621435 DOI: 10.1074/jbc.271.10.5698] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We have identified a potentially therapeutic anti-human immunodeficiency virus (HIV)-1 oligonucleotide composed entirely of deoxyguanosines and thymidines (T30177, also known as AR177: 5'-g.tggtgggtgggtggg.t-3', where asterisk indicates phosphorothioate linkage). In acute assay systems using human T-cells, T30177 and its total phosphodiester homologue T30175 inhibited HIV-1-induced syncytium production by 50% at 0.15 and 0.3 microM, respectively. Under physiological conditions, the sequence and composition of the 17-mer favors the formation of a compact, intramolecularly folded structure dominated by two stacked guanine quartet motifs that are connected by three loops of TGs. The molecule is stabilized by the coordination of a potassium ion between the two stacked quartets. We now show that these guanine quartet-containing oligonucleotides are highly resistant to serum nucleases, with t1/2 of 5 h and >4 days for T30175 and T30177, respectively. Both oligonucleotides were internalized efficiently by cells, with intracellular concentrations reaching 5-10-fold above the extracellular levels after 24 h of incubation. In contrast, single-base mutated variants or random sequence control oligonucleotides that could not form the compactly folded structure had markedly reduced half-lives (t1/2 from approximately 3 to 7 min), low cellular uptake, and no sequence-specific anti-HIV-1 activity. These data suggest that the tertiary structure of an oligonucleotide is a key determinant of its nuclease resistance, cellular uptake kinetics, and biological efficacy.
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Comparative Study |
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91 |
5
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Macejak DG, Jensen KL, Jamison SF, Domenico K, Roberts EC, Chaudhary N, von Carlowitz I, Bellon L, Tong MJ, Conrad A, Pavco PA, Blatt LM. Inhibition of hepatitis C virus (HCV)-RNA-dependent translation and replication of a chimeric HCV poliovirus using synthetic stabilized ribozymes. Hepatology 2000; 31:769-76. [PMID: 10706571 DOI: 10.1002/hep.510310331] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Ribozymes are catalytic RNA molecules that can be designed to cleave specific RNA sequences. To investigate the potential use of synthetic stabilized ribozymes for the treatment of chronic hepatitis C virus (HCV) infection, we designed and synthesized hammerhead ribozymes targeting 15 conserved sites in the 5' untranslated region (UTR) of HCV RNA. This region forms an internal ribosome entry site that allows for efficient translation of the HCV polyprotein. The 15 synthetic ribozymes contained modified nucleotides and linkages that stabilize the molecules against nuclease degradation. All 15 ribozymes were tested for their ability to reduce expression in an HCV 5' UTR/luciferase reporter system and for their ability to inhibit replication of an HCV-poliovirus (HCV-PV) chimera. Treatment with several ribozymes resulted in significant down-regulation of HCV 5' UTR/luciferase reporter expression (range 40% to 80% inhibition, P <.05). Moreover, several ribozymes showed significant inhibition (>90%, P <.001) of chimeric HCV-PV replication. We further show that the inhibitory activity of ribozymes targeting site 195 of HCV RNA exhibits a sequence-specific dose response, requires an active catalytic ribozyme core, and is dependent on the presence of the HCV 5' UTR. Treatment with synthetic stabilized anti-HCV ribozymes has the potential to aid patients who are infected with HCV by reducing the viral burden through specific targeting and cleavage of the viral genome.
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90 |
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Dyble M, Salali GD, Chaudhary N, Page A, Smith D, Thompson J, Vinicius L, Mace R, Migliano AB. Human behavior. Sex equality can explain the unique social structure of hunter-gatherer bands. Science 2015; 348:796-8. [PMID: 25977551 DOI: 10.1126/science.aaa5139] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The social organization of mobile hunter-gatherers has several derived features, including low within-camp relatedness and fluid meta-groups. Although these features have been proposed to have provided the selective context for the evolution of human hypercooperation and cumulative culture, how such a distinctive social system may have emerged remains unclear. We present an agent-based model suggesting that, even if all individuals in a community seek to live with as many kin as possible, within-camp relatedness is reduced if men and women have equal influence in selecting camp members. Our model closely approximates observed patterns of co-residence among Agta and Mbendjele BaYaka hunter-gatherers. Our results suggest that pair-bonding and increased sex egalitarianism in human evolutionary history may have had a transformative effect on human social organization.
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Research Support, Non-U.S. Gov't |
10 |
90 |
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Reeves WH, Chaudhary N, Salerno A, Blobel G. Lamin B autoantibodies in sera of certain patients with systemic lupus erythematosus. J Exp Med 1987; 165:750-62. [PMID: 3546581 PMCID: PMC2188284 DOI: 10.1084/jem.165.3.750] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Sera from four patients with systemic lupus erythematosus containing antibodies that yield nuclear rim staining of HEp-2 cells by indirect immunofluorescence were identified and characterized. Each serum contained autoantibodies reacting strongly with lamin B on western blots. One of the four sera displayed weaker reactivity with lamins A and C, while the other three displayed only minimal reactivity with lamins A and C. Titers of antilamin antibodies ranged from 1:1,250 to 1:36,250. Two of the sera also reacted at a dilution of 1:20 with cytoplasmic filaments of PTK-2 cells, suggesting that a small fraction of the autoantibodies in these sera may bind to alpha-helical domains of the lamins that are homologous to those of intermediate filaments. The majority of the antilamin antibodies in these patients' sera are specific for portions of the lamin B molecule that are not homologous to lamins A and C, however. The findings suggest that autoantibodies to the nuclear lamina may, in some instances, be responsible for a rim pattern in the fluorescent antinuclear antibody assay. In addition, autoantibodies to the nuclear lamina in sera of certain patients with systemic lupus erythematosus may be useful for defining the molecular structure and biological functions of lamin B, as well as for studying mechanisms of autoimmunity.
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research-article |
38 |
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8
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Ghaziuddin N, King CA, Naylor MW, Ghaziuddin M, Chaudhary N, Giordani B, Dequardo JR, Tandon R, Greden J. Electroconvulsive treatment in adolescents with pharmacotherapy-refractory depression. J Child Adolesc Psychopharmacol 1996; 6:259-71. [PMID: 9231319 DOI: 10.1089/cap.1996.6.259] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The effectiveness and safety of ECT in pharmacotherapy-refractory depression was examined in 11 hospitalized adolescents (ages 16.3 +/- 1.7 years, 10 females) with a primary DSM-III-R diagnosis of mood disorder, which had failed to respond to three or more adequate trials of antidepressant pharmacotherapy. After a thorough diagnostic evaluation, patients received a course of ECT involving 11.2 +/- 2.0 (range 8-15) administrations. ECT was commenced with bilateral treatment in 2 adolescents and nondominant right electrode placement in 9 patients; 5 of the 9 patients were subsequently changed to bilateral treatment. All 11 patients improved to a clinically significant degree. Significant improvements were noted in scores on the Children Depression Rating Scale-Revised (CDSR-R) and the Global Assessment of Functioning Scale (GAF) (p < 0.05). Euthymia, defined as CDRS-R score < or = 40, was achieved by 64% (7/11) of patients. The Mini-Mental State Examination showed no significant decline in cognitive functioning. Neuropsychological testing completed in 5 subjects both before ECT and 1-5 days after the last treatment, indicated a significant decline in attention, concentration, and long-term memory search. Minor side effects, experienced within the first 12 hours of treatment, were headache (80% of patients) and nausea/vomiting (64%). The potentially serious complication of tardive seizure (after full recovery of consciousness) occurred in 1 adolescent. Prolonged seizures (> 2.5 minutes) were noted in 7 of the 11 patients (9.6% of the 135 ECT administrations). Pending further research on ECT in youth, it is recommended that ECT should only be administered to youth in hospital settings, that all regularly administered psychotropic medications (including antidepressants) be discontinued before ECT and restarted after the final administration of ECT, and that physicians be aware that 12 treatments are usually sufficient, but that 15 treatments may occasionally be necessary for treating depressed adolescents. With the understanding that scientific evaluation of ECT in youth is lacking, it appears that ECT can be an effective and relatively safe treatment for depressed adolescents who have failed to respond to antidepressant pharmacotherapy.
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Clinical Trial |
29 |
51 |
9
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Guy-Caffey JK, Bodepudi V, Bishop JS, Jayaraman K, Chaudhary N. Novel polyaminolipids enhance the cellular uptake of oligonucleotides. J Biol Chem 1995; 270:31391-6. [PMID: 8537413 DOI: 10.1074/jbc.270.52.31391] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Two new polyaminolipids have been synthesized for the purpose of improving cellular uptake of oligonucleotides. The amphipathic compounds are conjugates of spermidine or spermine linked through a carbamate bond to cholesterol. The polyaminolipids are relatively nontoxic to mammalian cells. In tissue culture assays, using fluorescent-tagged or radiolabeled triple helix-forming oligonucleotides, spermine-cholesterol and spermidine-cholesterol significantly enhance cellular uptake of the oligomers in the presence of serum. Spermine-cholesterol is comparable with DOTMA/DOPE (a 1:1 (w/w) formulation of the cationic lipid N-[1-(2,3-dioleyloxy)-propyl]-N,N,N-trimethylammonium chloride (DOTMA) and the neutral lipid dioleylphosphatidylethanolamine (DOPE)) in increasing cellular uptake of oligonucleotides, while spermidine-cholesterol is more efficient. The internalized oligonucleotides are routed to the nucleus as early as 20 min after treatment, suggesting that the polyaminolipids increase the permeability of cellular membranes to oligonucleotides. At later times, much of the incoming oligonucleotides are sequestered within punctate cytoplasmic granules, presumably compartments of endosomal origin. Coadministration with polyaminolipids markedly improves the cellular stability of the oligonucleotides; more than 80% of the material can be recovered intact up to 24 h after addition to cells. In the absence of the polyaminolipids, nearly all of the material is degraded within 6 h. These data suggest that the new polyaminolipids may be useful for the delivery of nucleic acid-based therapeutics into cells.
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Gemmete JJ, Chaudhary N, Elias AE, Toma AK, Pandey AS, Parker RA, Davagnanam I, Maher CO, Brew S, Robertson F. Spinal dural arteriovenous fistulas: clinical experience with endovascular treatment as a primary therapy at 2 academic referral centers. AJNR Am J Neuroradiol 2013; 34:1974-9. [PMID: 23620076 DOI: 10.3174/ajnr.a3522] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Spinal dural arteriovenous fistulas are a rare entity that, if left untreated, can lead to considerable morbidity with progressive spinal cord symptoms. The aim of this study was to evaluate the clinical outcome of patients with spinal dural arteriovenous fistulas that were primarily treated with endovascular embolization. MATERIALS AND METHODS A retrospective review was performed of all patients from 1997-2010 who underwent treatment at 2 academic referral centers for a spinal dural arteriovenous fistula. Follow-up was performed by clinical examination, and functional status was measured by use of the Aminoff-Logue Disability Scale, McCormick classification grading, and mRS scores. The nonparametric Wilcoxon signed rank test was used to compare pretreatment and posttreatment Aminoff-Logue Disability Scale gait and micturition scores, McCormick classification grading, and mRS scores. P values < .05 were considered significant. RESULTS A total of 38 patients were included. Five patients (2 endovascular, 3 surgical) were lost to follow-up and therefore were excluded from the analysis, 29 patients were initially treated from an endovascular approach (9 Onyx, 20 cyanoacrylate), and 4 patients were treated from a standard surgical approach. Five patients in the endovascular group subsequently underwent surgery for various reasons. The clinical improvements in the Aminoff-Logue Disability Scale gait and micturition scores, McCormick classification grading, and the mRS scores were statistically significant (P < .05, Wilcoxon signed rank test). CONCLUSIONS We conclude that endovascular treatment of spinal dural arteriovenous fistulas can result in good clinical outcomes. Surgery remains the treatment of choice when safe embolization of the proximal radicular draining vein cannot be obtained or because the shunting artery of the spinal dural arteriovenous fistula also supplies the anterior spinal, posterior spinal, or a radiculomedullary artery.
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Multicenter Study |
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38 |
11
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Shah H, Gemmete JJ, Chaudhary N, Pandey AS, Ansari SA. Acute life-threatening hemorrhage in patients with head and neck cancer presenting with carotid blowout syndrome: follow-up results after initial hemostasis with covered-stent placement. AJNR Am J Neuroradiol 2011; 32:743-7. [PMID: 21436338 DOI: 10.3174/ajnr.a2379] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND AND PURPOSE CSP in patients with HNC presenting with CBS can provide immediate hemostasis to prevent exsanguination. We evaluated the safety and efficacy of CSP to control acute life-threatening hemorrhage in patients with HNC presenting with CBS. MATERIALS AND METHODS We retrospectively reviewed 10 patients (7 men, 3 women; mean age, 59 years) with HNC presenting with acute life-threatening hemorrhage from CBS that was treated with CSP. We studied patient demographics, presentations, procedures, initial and delayed complications, and technical and clinical outcomes on follow-up. RESULTS All patients achieved immediate hemostasis following CSP. Periprocedural complications consisted of groin hematomas (n=2), acute limb ischemia requiring thrombectomy, and an asymptomatic temporal lobe hemorrhage. Imaging and clinical follow-up were available for a mean of 17.7 months (range, 1-60 months). Two patients remained asymptomatic with a patent stent and no evidence of rebleeding at 17 and 21 months, respectively. Recurrent hemorrhages requiring retreatment were encountered in 3 patients secondary to stent infections (30%) at mean duration of 8 months. Neurologic morbidity resulted from stent thrombosis and stroke at 8 months in a single patient. Mortality was unrelated to CSP but was a result of palliative hospice care (n=3) at a mean of 2 months or natural disease progression (n=1) with documented patency of the stent at 6 months. CONCLUSIONS Acute life-threatening hemorrhage from CBS related to advanced HNC can be safely and effectively treated with CSP. However, potential delayed ischemic or infectious complications are common in the exposed or infected neck.
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Journal Article |
14 |
37 |
12
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Chaudhary N, McMahon C, Blobel G. Primary structure of a human arginine-rich nuclear protein that colocalizes with spliceosome components. Proc Natl Acad Sci U S A 1991; 88:8189-93. [PMID: 1896467 PMCID: PMC52472 DOI: 10.1073/pnas.88.18.8189] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The cDNA for a 54-kDa nuclear protein (p54) has been cloned from a human hepatoma expression library. Contained within p54 is an arginine/serine-rich region similar to segments of several proteins that participate in pre-mRNA splicing including the 70-kDa component of U1 small nuclear and "suppressor-of-white-apricot" proteins. The arginine/serine-rich region is dominated by a series of 8-amino acid imperfect repetitive motifs (consensus sequence, Arg-Arg-Ser-Arg-Ser-Arg-Ser-Arg). Antibodies raised against synthetic peptides of p54 react with an approximately 70-kDa protein on immunoblots of HeLa cell and rat liver nuclear proteins. This apparent discrepancy in mass is also observed when p54 mRNA is translated in vitro. Indirect immunofluorescence studies in HeLa cells show that p54 is distributed throughout the nucleus in a speckled pattern, with an additional diffuse labeling of the nucleus excluding the nucleoli. Double immunofluorescence experiments indicate that these punctate regions are coincident with the speckles seen in cells stained with antibodies against several constituents of the pre-mRNA splicing machinery. Sedimentation analysis of HeLa cell extracts on sucrose gradients showed that p54 migrates at 4-6 S, indicating that the protein is not a tightly associated component of snRNPs. Although the function of p54 is not yet known, our structure and immunolocalization data suggest that this protein may have a role in pre-mRNA processing.
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research-article |
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37 |
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Chaudhary N, Freeman DJ, Rip JW, Carroll KK. Direct estimation of dolichyl phosphate in rat liver by high pressure liquid chromatography. Lipids 1982; 17:558-60. [PMID: 7132586 DOI: 10.1007/bf02535384] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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43 |
31 |
14
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Gemmete JJ, Chaudhary N, Pandey A, Gandhi D, Sullivan SE, Marentette LJ, Chepeha DB, Ansari SA. Usefulness of percutaneously injected ethylene-vinyl alcohol copolymer in conjunction with standard endovascular embolization techniques for preoperative devascularization of hypervascular head and neck tumors: technique, initial experience, and correlation with surgical observations. AJNR Am J Neuroradiol 2009; 31:961-6. [PMID: 20037136 DOI: 10.3174/ajnr.a1936] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Few reports have described the embolization of head and neck lesions by using direct percutaneous techniques. We report our preliminary experience in the direct percutaneous embolization of hypervascular head and neck tumors by using Onyx in conjunction with standard endovascular embolization techniques. We describe the technical aspects of the procedure and its efficacy in reducing intraoperative blood loss. MATERIALS AND METHODS We retrospectively studied 14 patients (3 females and 11 males; mean age, 33.4 years; range, 11-56 years) with 15 hypervascular tumors of the head and neck that underwent direct percutaneous embolization with Onyx in conjunction with particulate embolization. Nine paragangliomas and 6 JNAs underwent treatment. Documented blood loss was obtained from operative reports in these 15 patients with surgical resection performed 24-48 hours after the embolization. RESULTS Intratumoral penetration with progressive blood flow stasis was achieved during each injection. A mean of 3.1 needles (20-gauge, 3.5-inch spinal needle) were placed percutaneously into the lesion (range, 1-6). The mean intraoperative blood loss was 780 mL (range, <50-2200 mL). Near total angiographic devascularization was achieved in 13 of 15 tumors. There were no local complications or neurologic deficits from the percutaneous access or embolization of these hypervascular tumors. CONCLUSIONS In this study, the use of percutaneous injected Onyx in conjunction with standard endovascular embolization techniques in patients with hypervascular head and neck tumors seemed to enhance the ability to devascularize these tumors before operative removal.
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Journal Article |
16 |
29 |
15
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Mani J, Chaudhary N, Kanjalkar M, Shah PU. Cerebellar ataxia due to lead encephalopathy in an adult. J Neurol Neurosurg Psychiatry 1998; 65:797. [PMID: 9810963 PMCID: PMC2170333 DOI: 10.1136/jnnp.65.5.797] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Case Reports |
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29 |
16
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Chaudhary N, Jain A, Gudwani S, Kapoor R, Motwani G. Intramuscular haemangioma of head and neck region. J Laryngol Otol 1998; 112:1199-201. [PMID: 10209624 DOI: 10.1017/s0022215100142859] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Intramuscular haemangiomas are rare benign haemangiomas occurring within the skeletal muscle. These are uncommon tumours in the head and neck region and occur most frequently on the trunk and extremities. Fewer than 80 cases of intra-muscular haemangioma in the head and neck region have been reported in the literature. A case of intramuscular haemangioma of the sternocleidomastoid muscle is presented. The review of occurrence and natural history of such tumours is described and clinical and radiological presentation, histological classifications and treatment modalities are discussed.
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Case Reports |
27 |
25 |
17
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Griauzde J, Gemmete JJ, Chaudhary N, Wilson TJ, Pandey AS. Large-volume blood patch to multiple sites in the epidural space through a single-catheter access site for treatment of spontaneous intracranial hypotension. AJNR Am J Neuroradiol 2014; 35:1841-6. [PMID: 24788127 DOI: 10.3174/ajnr.a3945] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Spontaneous intracranial hypotension can be a therapeutic challenge to the treating physician. In this study, we present our experience with the administration of a large-volume blood patch to multiple sites in the epidural space through a single-catheter access site. MATERIALS AND METHODS A retrospective review was conducted of patients with spontaneous intracranial hypotension who underwent a large-volume blood patch to multiple sites in the epidural space through a single-catheter access site from 2010 to 2012. Patient demographic data, clinical charts, indications for treatment, radiographic images, procedure notes, and postprocedure hospital course were reviewed. RESULTS Overall, 9 patients were identified who underwent 20 blood patch procedures. Patients were selected to undergo the large-volume procedure either because they had a failed site-directed epidural blood patch or if imaging demonstrated multiple possible leak sites. There were 6 women and 3 men, with an average age of 33.5 years. The mean volume of blood injected per procedure was 54.1 mL (median=55 mL; range=38-70 mL). All patients had an orthostatic headache as one of their presenting symptoms; 22% also presented with neurocognitive decline and behavioral changes; 89% of patients had improvement or resolution of their symptoms; and 80% of patients who had a previously failed site-directed epidural blood or fibrin glue patch improved with a large volume catheter-directed blood patch. CONCLUSIONS Our experience supports the use of a large-volume blood patch to multiple sites in the epidural space through a single-catheter access site for the treatment of spontaneous intracranial hypotension. Additionally, our results indicate a role for this procedure in refractory cases of spontaneous intracranial hypotension.
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Journal Article |
11 |
23 |
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Rip JW, Chaudhary N, Carroll KK. Distribution and metabolism of dolichol and dolichyl phosphate in rat liver. CANADIAN JOURNAL OF BIOCHEMISTRY AND CELL BIOLOGY = REVUE CANADIENNE DE BIOCHIMIE ET BIOLOGIE CELLULAIRE 1983; 61:1025-31. [PMID: 6313169 DOI: 10.1139/o83-131] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The dolichol and dolichyl phosphate (Dol-P) content of various tissues and liver subcellular fractions obtained from rats have been measured directly using high pressure liquid chromatographic methods developed in this laboratory. Spleen contained the highest concentration of dolichol, while other tissues including serum had smaller amounts. Although considerable differences in homologue distribution patterns were observed among the tissues examined, a number of purified subcellular fractions obtained from liver (nuclei, mitochondria, cytosol, and microsomes) exhibited a single common pattern. Only some 5% of liver dolichol appeared in the microsomal compartment of the cell where glycoprotein formation occurs, while 50% of the dolichol in this tissue was found in a lysosome-enriched fraction. The concentrations of dolichol present in liver nuclei, mitochondria, whole microsomes (also rough and smooth, endoplasmic recticulum (RER and SER, respectively), and cytosol were considerably lower (on a protein basis) than those present in whole liver. Besides the lysosome-enriched fraction, only plasma membranes and Golgi contained dolichol at concentrations equal to or greater than those present in liver homogenates. The low concentrations of dolichol found in microsomes suggest that the amounts of dolichol available for Dol-P formation via the CTP-dependent kinase reaction may be rate limiting. Most of the Dol-P in liver could be recovered in the microsomal fraction. Dol-P accounted for 4 and 40% of the sum of alcohol + dolichyl fatty acyl ester + Dol-P forms present in whole liver and in microsomes, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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Bagga R, Chaudhary N, Kalra J. Rupture in an unscarred uterus during second trimester pregnancy termination with mifepristone and misoprostol. Int J Gynaecol Obstet 2004; 87:42-3. [PMID: 15464778 DOI: 10.1016/j.ijgo.2004.05.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2004] [Revised: 05/26/2004] [Accepted: 05/28/2004] [Indexed: 11/16/2022]
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Journal Article |
21 |
19 |
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Chaudhary N, Nakka KK, Chavali PL, Bhat J, Chatterjee S, Chattopadhyay S. SMAR1 coordinates HDAC6-induced deacetylation of Ku70 and dictates cell fate upon irradiation. Cell Death Dis 2014; 5:e1447. [PMID: 25299772 PMCID: PMC4237237 DOI: 10.1038/cddis.2014.397] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 08/11/2014] [Accepted: 08/14/2014] [Indexed: 11/30/2022]
Abstract
Acetylation status of DNA end joining protein Ku70 dictates its function in DNA repair and Bax-mediated apoptosis. Despite the knowledge of HDACs and HATs that are reported to modulate the acetylation dynamics of Ku70, very little is known about proteins that critically coordinate these key modifications. Here, we demonstrate that nuclear matrix-associated protein scaffold/matrix-associated region-binding protein 1 (SMAR1) is a novel interacting partner of Ku70 and coordinates with HDAC6 to maintain Ku70 in a deacetylated state. Our studies revealed that knockdown of SMAR1 results in enhanced acetylation of Ku70, which leads to impaired recruitment of Ku70 in the chromatin fractions. Interestingly, ionizing radiation (IR) induces the expression of SMAR1 and its redistribution as distinct nuclear foci upon ATM-mediated phosphorylation at serine 370. Furthermore, SMAR1 regulates IR-induced G2/M cell cycle arrest by facilitating Chk2 phosphorylation. Alternatively, SMAR1 provides radioresistance by modulating the association of deacetylated Ku70 with Bax, abrogating the mitochondrial translocation of Bax. Thus, we provide mechanistic insights of SMAR1-mediated regulation of repair and apoptosis via a complex crosstalk involving Ku70, HDAC6 and Bax.
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Research Support, Non-U.S. Gov't |
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Castañeda TR, Nogueiras R, Müller TD, Krishna R, Grant E, Jones A, Ottaway N, Ananthakrishnan G, Pfluger PT, Chaudhary N, Solomon MB, Woods SC, Herman JP, Tschöp MH. Decreased glucose tolerance and plasma adiponectin:resistin ratio in a mouse model of post-traumatic stress disorder. Diabetologia 2011; 54:900-9. [PMID: 21181395 DOI: 10.1007/s00125-010-2019-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2010] [Accepted: 11/25/2010] [Indexed: 10/18/2022]
Abstract
AIMS/HYPOTHESIS Obesity and type 2 diabetes are among the most serious health pathologies worldwide. Stress has been proposed as a factor contributing to the development of these health risk factors; however, the underlying mechanisms that link stress to obesity and diabetes need to be further clarified. Here, we study in mice how chronic stress affects dietary consumption and how that relationship contributes to obesity and diabetes. METHODS C57BL/6J mice were subjected to chronic variable stress (CVS) for 15 days and subsequently fed with a standard chow or high-fat diet. Food intake, body weight, respiratory quotient, energy expenditure and spontaneous physical activity were measured with a customised calorimetric system and body composition was measured with nuclear magnetic resonance. A glucose tolerance test was also applied and blood glucose levels were measured with a glucometer. Plasma levels of adiponectin and resistin were measured using Lincoplex kits. RESULTS Mice under CVS and fed with a high-fat diet showed impaired glucose tolerance associated with low plasma adiponectin:resistin ratios. CONCLUSIONS/INTERPRETATION This study demonstrates, in a novel mouse model, how post-traumatic stress disorder enhances vulnerability for impaired glucose metabolism in an energy-rich environment and proposes a potential adipokine-based mechanism.
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Rupar CA, Rip JW, Chaudhary N, Carroll KK. The subcellular localization of enzymes of dolichol metabolism in rat liver. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(19)81077-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Gemmete JJ, Patel S, Pandey AS, Sullivan SE, McKean EL, Marentette LJ, Chaudhary N. Preliminary experience with the percutaneous embolization of juvenile angiofibromas using only ethylene-vinyl alcohol copolymer (Onyx) for preoperative devascularization prior to surgical resection. AJNR Am J Neuroradiol 2012; 33:1669-75. [PMID: 22499846 DOI: 10.3174/ajnr.a3043] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Juvenile angiofibromas are hypervascular tumors that may benefit from preoperative devascularization to reduce intraoperative blood loss. Our purpose was to evaluate the extent of angiographic devascularization and intraoperative blood loss by using only Onyx for percutaneous juvenile angiofibroma tumor embolization. MATERIALS AND METHODS We reviewed the clinical records and preoperative and postoperative imaging studies of a consecutive series of 9 patients with juvenile angiofibromas who were treated with preoperative embolization with direct percutaneous injection of Onyx followed by resection from a standard open surgical or endoscopic approach. RESULTS Two Fisch type I, 1 Fisch type II, 5 Fisch type IIIa, and 1 Fisch type IVa tumor were treated. Complete devascularization was achieved in all cases percutaneously with only Onyx. There were no complications. The average intraoperative blood loss was 567.7 mL (range, 10-1700 mL). An average of 2.2 needles (range, 1-5 needles) was placed into the tumor. An average of 14.6 mL of Onyx (range, 2-25 mL) was injected into each tumor. Four Fisch type IIIa tumors were removed completely from only an ENE approach. CONCLUSIONS Presurgical direct percutaneous embolization of a juvenile angiofibroma with only EVOH before surgical resection is safe and feasible. Our preliminary experience suggests that Onyx may offer a higher degree of devascularization compared with other embolic agents. This may facilitate an easier surgical resection with lower blood loss.
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Connor SEJ, Chaudhary N, Fareedi S, Woo EK. Imaging of muscular denervation secondary to motor cranial nerve dysfunction. Clin Radiol 2006; 61:659-69. [PMID: 16843749 DOI: 10.1016/j.crad.2006.04.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2006] [Revised: 03/30/2006] [Accepted: 04/04/2006] [Indexed: 11/27/2022]
Abstract
The effects of motor cranial nerve dysfunction on the computed tomography (CT) and magnetic resonance imaging (MRI) appearances of head and neck muscles are reviewed. Patterns of denervation changes are described and illustrated for V, VII, X, XI and XII cranial nerves. Recognition of the range of imaging manifestations, including the temporal changes in muscular appearances and associated muscular grafting or compensatory hypertrophy, will avoid misinterpretation as local disease. It will also prompt the radiologist to search for underlying cranial nerve pathology, which may be clinically occult. The relevant cranial nerve motor division anatomy will be described to enable a focussed search for such a structural abnormality.
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Chaudhary N, Ferguson S, Herbel S. Tennessee's Novice Driver Safety Project: a program to increase parental involvement. TRAFFIC INJURY PREVENTION 2004; 5:356-361. [PMID: 15545074 DOI: 10.1080/15389580490522531] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Graduated licensing has been implemented in many U.S. states to reduce teenage driver crash involvement. The goal is to introduce teenagers gradually to driving before allowing full, unrestricted licensure. Tennessee, one of the states that introduced graduated licensing, implemented a program to influence both driving by teenagers during the learner stage and restrictions imposed by parents after licensure. In addition to a standard welcome letter, booklets and reminder cards were mailed to parents of teenagers who had just obtained their learner's permits. The booklets and cards were designed to assist parents in becoming more actively involved in their children's driving experiences. The effects of three different approaches (welcome letter only, letter plus booklet, and letter plus booklet plus reminder cards) on parental involvement, teenage crashes, and teenage citations were assessed based on telephone interviews with parents. Although the parents said the booklets and reminder cards were helpful and should continue to be sent to other parents, there were no discernible effects on teenage practice driving and reported parental involvement during the learner stage. Nor was there any measurable influence on restrictions imposed by parents after licensure. It is unknown whether the standard welcome letter affected parental involvement, but overall supervised driving exceeded the state requirements by a substantial margin.
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