101
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Wymer N, Buchanan LV, Henderson D, Mehta N, Botting CH, Pocivavsek L, Fierke CA, Toone EJ, Naismith JH. Directed evolution of a new catalytic site in 2-keto-3-deoxy-6-phosphogluconate aldolase from Escherichia coli. Structure 2001; 9:1-9. [PMID: 11342129 DOI: 10.1016/s0969-2126(00)00555-4] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
BACKGROUND Aldolases are carbon bond-forming enzymes that have long been identified as useful tools for the organic chemist. However, their utility is limited in part by their narrow substrate utilization. Site-directed mutagenesis of various enzymes to alter their specificity has been performed for many years, typically without the desired effect. More recently directed evolution has been employed to engineer new activities onto existing scaffoldings. This approach allows random mutation of the gene and then selects for fitness to purpose those proteins with the desired activity. To date such approaches have furnished novel activities through multiple mutations of residues involved in recognition; in no instance has a key catalytic residue been altered while activity is retained. RESULTS We report a double mutant of E. coli 2-keto-3-deoxy-6-phosphogluconate aldolase with reduced but measurable enzyme activity and a synthetically useful substrate profile. The mutant was identified from directed-evolution experiments. Modification of substrate specificity is achieved by altering the position of the active site lysine from one beta strand to a neighboring strand rather than by modification of the substrate recognition site. The new enzyme is different to all other existing aldolases with respect to the location of its active site to secondary structure. The new enzyme still displays enantiofacial discrimination during aldol addition. We have determined the crystal structure of the wild-type enzyme (by multiple wavelength methods) to 2.17 A and the double mutant enzyme to 2.7 A resolution. CONCLUSIONS These results suggest that the scope of directed evolution is substantially larger than previously envisioned in that it is possible to perturb the active site residues themselves as well as surrounding loops to alter specificity. The structure of the double mutant shows how catalytic competency is maintained despite spatial reorganization of the active site with respect to substrate.
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Affiliation(s)
- N Wymer
- Department of Chemistry, LSRC, Duke University, Durham, NC 27708, USA
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102
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Abstract
A series of in vitro and in vivo assays have been conducted using FAVOR PAC (CAS Registry No. 9003-04-7), a cross-linked sodium polyacrylate polymer, to test its ability to induce mutations. FAVOR PAC is a member of the FAVOR family of superabsorbent polymers (SAPs) developed by Stockhausen GmbH & Co KG (Krefeld, Germany). These SAPs are known for their ability to retain large volumes of fluid, even against pressure. The genotoxic potential of FAVOR PAC and its extracts was examined in the following five standard mutagenicity assays: the Salmonella typhimurium and Escherichia coli reverse mutation assay, the mouse lymphoma fluctuation assay, the mouse lymphoma forward mutation assay, the in vivo mouse micronucleus assay, and an in vitro rat DNA synthesis assay. Based on the results of these assays, it was concluded that FAVOR PAC was clearly not genotoxic under any of the conditions of the mutagenicity assays performed.
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Affiliation(s)
- J Haselbach
- Stockhausen GmbH & Co KG, 47704 Krefeld, Germany
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103
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Mehta N, Macintosh I, Rivers R, Nadel S. Acute chest syndrome of sickle cell disease. J Pediatr 2000; 137:589; author reply 590. [PMID: 11035847 DOI: 10.1067/mpd.2000.107634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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104
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Sandler RS, Cummings MS, Keku TO, Terse A, Mehta N. Disposable versus reusable biopsy forceps for colorectal epithelial cell proliferation in humans. Cancer Epidemiol Biomarkers Prev 2000; 9:1123-5. [PMID: 11045798] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
The performance of various measures of rectal mucosal proliferation has been evaluated in the literature, but the performance of the forceps used to obtain the tissue has received little attention. We used data from two large studies of proliferation at a single institution to compare reusable and disposable endoscopic forceps. Endoscopic pinch biopsies were taken 10 cm from the anal verge using either reusable or disposable, oval-cupped, sheathed forceps. The specimens were fixed, embedded, and sectioned, taking care to orient the specimens longitudinally. Five sections were placed on each slide. We determined how many slides did not contain eight scorable crypts (inadequate) and how many sections were necessary to identify eight complete crypts. There were 395 subjects who had biopsies taken with reusable forceps and 185 subjects who had biopsies taken with disposable forceps. The specimens were inadequate in 27.6% of the reusable forceps specimens versus 2.7% of the disposable forceps (P < 0.0001). The mean number of tissue sections necessary to identify eight scorable crypts for the reusable forceps was 3.82 (SD, 0.87) compared with 3.17 (SD, 0.83) for disposable forceps (P = 0.0001). The specimens taken with the disposable forceps were better, probably because the forceps were sharper. We believe that the better quality of the specimens and the sterility justify the higher cost of disposable forceps. We would urge investigators in proliferation studies to evaluate the biopsy equipment as carefully as they evaluate other aspects of their methods.
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Affiliation(s)
- R S Sandler
- Center for Gastrointestinal Biology and Disease, School of Medicine, University of North Carolina at Chapel Hill, 27514, USA.
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105
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Abstract
While many other illnesses affecting children have been contained or even eliminated, meningococcal disease has become a leading infectious cause of death. The major management challenge may be increased intracranial pressure or toxic shock, depending on whether meningitis or septicemia predominates. A new protein-conjugated group C vaccine is expected to reduce deaths by as much as 40%.
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Affiliation(s)
- N Mehta
- Department of Pediatrics, St. Mary's Hospital, London, United Kingdom
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106
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Porcelli P, Schanler R, Greer F, Chan G, Gross S, Mehta N, Spear M, Kerner J, Euler AR. Growth in human milk-Fed very low birth weight infants receiving a new human milk fortifier. Ann Nutr Metab 2000; 44:2-10. [PMID: 10838460 DOI: 10.1159/000012814] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND/AIMS Human milk fortification has been advocated to enhance premature infants' growth. We, therefore, undertook this study of a new human milk fortifier containing more protein than a reference one. METHODS Open, randomized, controlled, multiclinic trial, with weekly growth parameters and safety evaluations in premature infants <1,500 g. RESULTS The 2 groups did not differ in demographic and baseline characteristics. The adjusted daily milk intake was significantly higher in the infants fed reference human milk fortifier (n = 29; 154.2 +/- 2.1 vs. 144.4 +/- 2.5 ml/kg/day, mean +/- SE; p < 0.05). Both human milk fortifiers produced increases over baseline in weight, length, and head circumference, with greater gains observed in the new human milk fortifier-fed infants for the former two parameters (weight gain 26.8 +/- 1.3 and 20.4 +/- 1.2 g/day, p < 0.05; head circumference 1.0 +/- 0.1 and 0.8 +/- 0.1 cm/week; length 0.9 +/- 0.1 and 0.8 +/- 0.1 cm/week, respectively). Serum chemistries were normal and acceptable for age. Study events were typical for premature infants and similar in both groups. CONCLUSIONS This new human milk fortifier had comparable safety to the reference human milk fortifier and promoted faster weight gain and head circumference growth.
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Affiliation(s)
- P Porcelli
- Department of Pediatrics, Bowman Gray School of Medicine, Winston-Salem, N.C, USA
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107
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Mehta N, Termine JE. Biographies of the first lecturers at the Long Island College Hospital, the first medical school in Brooklyn. J Med Biogr 2000; 8:162-168. [PMID: 10954925 DOI: 10.1177/096777200000800307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Affiliation(s)
- N Mehta
- Department of Internal Medicine, Long Island College Hospital, Brooklyn, NY 11201, USA
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108
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Cooney A, Mehta N. Paediatric intensive care. Br J Anaesth 2000; 85:179. [PMID: 10928017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
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109
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Cooney A, Mehta N. Chemoprophylaxis for meningococcal disease in healthcare workers. Anaesthesia 2000; 55:590-1. [PMID: 10866726 DOI: 10.1046/j.1365-2044.2000.01479-3.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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110
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Mehta N, Nadel S, Levin M, Britto J. Haemophagocytic lymphohistiocytosis (HLH) on the intensive care unit. Br J Anaesth 2000. [DOI: 10.1093/bja/84.5.678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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111
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Mehta N, Nadel S, Reeve A, Nadel A, Britto J. Peripherally inserted central venous catheters (PICC). Br J Anaesth 2000. [DOI: 10.1093/bja/84.5.677-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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112
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Abstract
Metastasis to the pancreas from a distant primary cancer is uncommon, most cases being detected in the advanced stages of disease, often multiple in number, and diffusely displayed beyond surgical salvage. A solitary metastasis in the head of the pancreas is rarely encountered and although potentially amenable to surgical resection, surgeons are hesitant to perform pancreaticoduodenectomy for metastatic disease. Renal cell carcinoma is one malignancy with a propensity to metastasize to the pancreas. We report herein the case of a solitary pancreatic metastasis from renal cell carcinoma successfully treated by pancreaticoduodenectomy in a middle-aged man. A discussion on the indications and effectiveness of performing pancreaticoduodenectomy for metastatic renal cell carcinoma is also presented.
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Affiliation(s)
- N Mehta
- State University of New York at Buffalo School of Medicine and Biomedical Sciences, Department of Surgery, Buffalo General Hospital, 14203, USA
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113
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Refolo LM, Eckman C, Prada CM, Yager D, Sambamurti K, Mehta N, Hardy J, Younkin SG. Antisense-induced reduction of presenilin 1 expression selectively increases the production of amyloid beta42 in transfected cells. J Neurochem 1999; 73:2383-8. [PMID: 10582597 DOI: 10.1046/j.1471-4159.1999.0732383.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [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: 11/20/2022]
Abstract
Autosomal dominant mutations in the presenilin 1 (PS1) gene are associated with familial, early-onset Alzheimer's disease. Although the pathogenic mechanism of these mutations is unclear, their common feature is that they lead to an increased concentration of amyloid beta-peptide (Abeta) 42 in the plasma of early-onset patients, in the conditioned media of transfected cells, and in the brains of transgenic mice that overexpress mutant PS1. To address the mechanism(s) by which the pathogenic PS1 mutations increase Abeta42, we constructed human cell lines expressing a doxycyclin (dox)-inducible antisense PS1 RNA and measured its effects on the levels of PS1, amyloid precursor protein (APP), and Abeta. In time course experiments, we observed a statistically significant (p = 0.0038) more than twofold elevation in secreted Abeta42 as early as 12 days after addition of dox. This correlated with an 80% decrease in the 46-kDa PS1 holoprotein and a 30% decrease in the 26-kDa N-terminal fragment (NTF). Furthermore, there was a significant fivefold (p = 0.002) increase in Abeta42 after 14-day dox treatment; this correlated with a >90% decrease in PS1 holoprotein and 60% decrease in NTF. At no time point did we observe significant changes in Abeta40, APP holoprotein, presenilin 2, or tubulin. Ten days after the removal of dox, we observed a return to constitutive levels for Abeta42, PS1 holoprotein, and NTF. These results suggest that in human cell lines, the reduction of normal PS1 activity results in the increased production of Abeta42. Furthermore, our results are consistent with a loss of function or dominant negative mechanism for the pathogenic PS1 mutations.
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Affiliation(s)
- L M Refolo
- Department of Pharmacology, Mayo Clinic Jacksonville, Florida 32224, USA
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114
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Buchanan LV, Mehta N, Pocivavsek L, Niranjanakumari S, Toone EJ, Naismith JH. Initiating a structural study of 2-keto-3-deoxy-6-phosphogluconate aldolase from Escherichia coli. Acta Crystallogr D Biol Crystallogr 1999; 55:1946-8. [PMID: 10531504 DOI: 10.1107/s0907444999011166] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
2-Keto-3-deoxy-6-phosphogluconate aldolase (KDPG aldolase, E.C. 4.1. 2.14) is a member of the pyruvate/phosphoenolpyruvate aldolase family. It is also a synthetically useful enzyme, capable of catalyzing the stereoselective aldol addition of pyruvate to a range of unnatural electrophilic substrates. The recombinant protein was purified by a two-step HPLC protocol involving anion-exchange and hydrophobic chromatography. Dynamic light-scattering experiments indicated the protein to be monodisperse. Crystals were obtained using the sitting-drop vapour-diffusion method, with PEG 6K as precipitant. Diffraction data were collected on a frozen crystal to a resolution of 2.26 A on station PX9.6 at the Daresbury synchrotron. The crystal belongs to space group P2(1)2(1)2(1), with unit-cell parameters a = 53.2, b = 77.9, c = 146.8 A.
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Affiliation(s)
- L V Buchanan
- Centre for Biomedical Sciences, North Haugh, The University, St Andrews, Fife KY16 9ST, Scotland
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115
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Abstract
The Internet can be useful for physicians, but beginning users are apt to encounter two problems: too much irrelevant information, and difficulty finding the desired information. This paper offers some practical tips that can prevent frustration and wasted time when searching for medical information on the Internet.
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Affiliation(s)
- N Mehta
- Department of General Internal Medicine, Cleveland Clinic, USA.
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116
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Dickson DW, Liu W, Hardy J, Farrer M, Mehta N, Uitti R, Mark M, Zimmerman T, Golbe L, Sage J, Sima A, D'Amato C, Albin R, Gilman S, Yen SH. Widespread alterations of alpha-synuclein in multiple system atrophy. Am J Pathol 1999; 155:1241-51. [PMID: 10514406 PMCID: PMC1867032 DOI: 10.1016/s0002-9440(10)65226-1] [Citation(s) in RCA: 226] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Glial cytoplasmic inclusions (GCI) are the hallmark of multiple system atrophy (MSA), a rare movement disorder frequently associated with autonomic dysfunction. In this study of 21 cases of MSA, GCI were consistently immunoreactive for alpha-synuclein and double-immunostained for ubiquitin and oligodendroglial markers, but not glial fibrillary acidic protein. No statistically significant difference was found in the density of GCI in various brain regions in the two forms of MSA, striatonigral degeneration (SND) and olivopontocerebellar atrophy (OPCA). Postmortem brain samples from 9 cases of MSA were fractionated according to solubility in buffer, Triton-X 100, sodium dodecyl sulfate (SDS), and formic acid, and alpha-synuclein immunoreactivity was measured in Western blots. Total alpha-synuclein immunoreactivity was increased in MSA compared to controls, with no statistically significant difference between SND and OPCA. Most of the increase was due to alpha-synuclein in SDS fractions. In controls this fraction had little or no immunoreactivity. In 7 cases and 4 controls correlations were investigated between quantitative neuropathology and biochemical properties of alpha-synuclein. Surprisingly, the amount of SDS-soluble alpha-synuclein correlated poorly with the number of GCI in adjacent sections. Furthermore, areas with few or no GCI unexpectedly had abundant SDS-soluble alpha-synuclein. These findings provide evidence that modifications of alpha-synuclein in MSA may be more widespread than obvious histopathology. Moreover, these alterations may constitute a biochemical signature for the synucleinopathies.
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Affiliation(s)
- D W Dickson
- Department of Pathology, Mayo Clinic Jacksonville, Jacksonville, Florida, USA.
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118
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Scrivani SJ, Keith DA, Kulich R, Mehta N, Maciewicz RJ. Posttraumatic gustatory neuralgia: a clinical model of trigeminal neuropathic pain. J Orofac Pain 1999; 12:287-92. [PMID: 10425975] [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: 02/13/2023]
Abstract
Six cases are reported in which the primary complaint was episodic, recurrent facial pain that was triggered by a taste stimulus. The pain first occurred days to weeks after head and neck surgery. Patients reported that a food stimulus placed in the mouth evoked episodic, electric shock-like pain in a preauricular location on the surgical side. The smell of food or, less reliably, emotional excitement could also trigger pain. Mandibular movement did not evoke the pain, and between lancinating attacks there was either no pain or only mild discomfort. Following an episode of pain, there was a refractory period during which the pain could not be elicited. Physical examination demonstrated a preauricular sensory loss of variable distribution. No abnormal sweating or vasomotor findings were clinically apparent. No odontogenic, muscular, salivary gland, neurologic, or psychologic pathology was found to explain the clinical symptoms. The pain was not relieved with standard doses of anticonvulsants that are commonly used to treat trigeminal neuralgia. The duration of the recurrent pain symptoms in this group was 8 to 132 months without remission. Gustatory neuralgia may be a discrete syndrome that results from abnormal interactions between salivary efferent fibers and trigeminal sensory afferent fibers in the injured auriculotemporal nerve. The unique features of the disorder make it a potentially useful clinical model for the investigation of autonomic/sensory interactions in neuropathic pain.
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Affiliation(s)
- S J Scrivani
- Department of Oral and Maxillofacial Surgery, Columbia-Presbyterian Medical Center, School of Dental and Oral Surgery, New York, New York 10032, USA
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119
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Ostrerova N, Petrucelli L, Farrer M, Mehta N, Choi P, Hardy J, Wolozin B. alpha-Synuclein shares physical and functional homology with 14-3-3 proteins. J Neurosci 1999; 19:5782-91. [PMID: 10407019 PMCID: PMC6783081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Abstract
alpha-Synuclein has been implicated in the pathophysiology of many neurodegenerative diseases, including Parkinson's disease (PD) and Alzheimer's disease. Mutations in alpha-synuclein cause some cases of familial PD (Polymeropoulos et al., 1997; Kruger et al., 1998). In addition, many neurodegenerative diseases show accumulation of alpha-synuclein in dystrophic neurites and in Lewy bodies (Spillantini et al., 1998). Here, we show that alpha-synuclein shares physical and functional homology with 14-3-3 proteins, which are a family of ubiquitous cytoplasmic chaperones. Regions of alpha-synuclein and 14-3-3 proteins share over 40% homology. In addition, alpha-synuclein binds to 14-3-3 proteins, as well as some proteins known to associate with 14-3-3, including protein kinase C, BAD, and extracellular regulated kinase, but not Raf-1. We also show that overexpression of alpha-synuclein inhibits protein kinase C activity. The association of alpha-synuclein with BAD and inhibition of protein kinase C suggests that increased expression of alpha-synuclein could be harmful. Consistent with this hypothesis, we observed that overexpression of wild-type alpha-synuclein is toxic, and overexpression of alpha-synuclein containing the A53T or A30P mutations exhibits even greater toxicity. The activity and binding profile of alpha-synuclein suggests that it might act as a protein chaperone and that accumulation of alpha-synuclein could contribute to cell death in neurodegenerative diseases.
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Affiliation(s)
- N Ostrerova
- Department of Pharmacology, Loyola University Medical Center, Maywood, Illinois 60153, USA
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120
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Abstract
BACKGROUND Although the liver is a potent tumor cell killing organ it is frequently the site of lethal metastases often signifying the endstage for patients with colorectal cancers. Enhancing hepatic-associated immunity remains elusive until the interactions among hepatic nonparenchymal cells (NPC) are deciphered. We sought to modulate the cellular components of the hepatic immune system of mice with anti-NK and anti-T-cell-neutralizing antibodies in order to determine the cell type most efficacious in preventing liver metastasis. MATERIALS AND METHODS Liver-derived murine colon adenocarcinoma (LD-MCA-38) cells were injected into the ileocolic vein (ICV) of immunocompetent and immunodeficient C57BL/6 mice. Mice were pretreated 1 day prior to tumor cell injection with one of three antibodies: anti-AsGM1, Anti-NK1.1, or Anti-Thy1.2. On Day 21 laparotomy was performed to determine the extent of hepatic tumor foci. The number of hepatic tumor foci was recorded and compared by the Wilcoxon rank sum test. RESULTS Mice pretreated with anti-AsGM1 or Anti-NK1.1 developed a massive increase in the number of hepatic tumor foci and decreased survival compared to the control treated mice. Pretreatment with anti-Thy1.2 antibody resulted in a significant decrease in the number of hepatic tumor foci. LD-MCA-38 tumor cells were unable to colonize the liver of C57BL/6 athymic nude mice; however, anti-AsGM1 antibody abolished this antimetastatic effect. There was no difference in the extent of hepatic metastasis and survival between immunodeficient C57BL/6 bg/bg and their conventional littermates bg/+. CONCLUSION AsGM1+ NK cells exhibit a significant antitumor response in the absence of T-cells. The concept of stimulating NK cell activity and suppressing T-cell function may enhance liver-associated immunity and serve as a deterrent for blood-borne tumor cells metastasizing to the liver.
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MESH Headings
- Adenocarcinoma/prevention & control
- Adenocarcinoma/secondary
- Animals
- Antibodies/pharmacology
- Antibodies, Monoclonal/pharmacology
- Antigens/immunology
- Antigens, Ly
- Antigens, Surface
- Colonic Neoplasms/pathology
- G(M1) Ganglioside/immunology
- G(M1) Ganglioside/metabolism
- Immunocompetence/physiology
- Killer Cells, Natural/metabolism
- Killer Cells, Natural/physiology
- Lectins, C-Type
- Liver Neoplasms/prevention & control
- Liver Neoplasms/secondary
- Lymphocyte Count/drug effects
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL/genetics
- Mice, Nude/immunology
- NK Cell Lectin-Like Receptor Subfamily B
- Neoplasm Invasiveness/prevention & control
- Neoplasm Transplantation
- Proteins/immunology
- T-Lymphocytes/pathology
- Thy-1 Antigens/immunology
- Tumor Cells, Cultured
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Affiliation(s)
- C M Volpe
- Department of Surgery, Buffalo VA Medical Center and CGF Health Systems, Buffalo, New York, 14203, USA.
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121
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Alkofide EA, Clark E, el-Bermani W, Kronman JH, Mehta N. The incidence and nature of fibrous continuity between the sphenomandibular ligament and the anterior malleolar ligament of the middle ear. J Orofac Pain 1999; 11:7-14. [PMID: 10332306] [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: 02/12/2023]
Abstract
The purpose of this study was to determine the structural interrelationship between the temporomandibular joint (TMJ) and the middle ear, in terms of fibrous continuity between the sphenomandibular ligament (SML) of the mandible and the anterior malleolar ligament (AML) of the middle ear. Thirty-seven specimens of the TMJ and middle ear were obtained from adult human cadavers. The temporal bone, petrotympanic fissure, mandibular fossa, and middle ear were dissected en bloc, fixed, sectioned, stained, and observed microscopically. Of the 37 specimens, 67.6% had a continuity of the SML through the fissure passing near the malleus of the middle ear. The AML was present at the fissure in 64.9% of the specimens, with 58.3% passing through and not stopping at the fissure. Results indicated a fibrous continuity between the SML and the AML. Structural differences between the two ligaments were also noted. The SML contained randomly arranged fibrous connective tissue with numerous interposed blood vessels. The AML had a smooth arrangement of fibers within the connective tissue, and few blood vessels were apparent. The clear anatomic relationship observed strongly supports the contention of a functional interrelationship between the TMJ and the middle ear.
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Affiliation(s)
- E A Alkofide
- Department of Orthodontics, Tufts University School of Dental Medicine Boston, Massachusetts 02111, USA
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122
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Tempe DK, Mulchandani P, Tandon MS, Mehta N, Tomar AS, Banerjee A, Khanna SK. Control of tachycardia and hypertension following coronary artery bypass graft surgery: efficacy and haemodynamic effects of esmolol. Indian Heart J 1999; 51:294-300. [PMID: 10624069] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Hypertension following coronary artery bypass grafting is not uncommon, especially in patients having good left ventricular function. It is often accompanied by tachycardia. The purpose of this study is to determine the efficacy of esmolol in the treatment of tachycardia and hypertension immediately following cardiopulmonary bypass and to study other haemodynamic effects of esmolol. Thirty patients undergoing elective [corrected] coronary artery bypass grafting were included in this prospective study. Morphine-based anaesthetic technique along-with standard bypass techniques were used in all the patients. The study was performed in the operating room about 30-45 minutes after the termination of cardiopulmonary bypass. Patients having a heart rate of more than 90 bpm and systolic blood pressure of more than 130 mm Hg without any inotropic support were included and randomly assigned to esmolol or control group. Esmolol was administered in a bolus dose of 500 micrograms/kg followed by infusion of upto 100 micrograms/kg/min. The patients in the control group were administered comparable volumes of normal saline. Baseline haemodynamic measurements were obtained just before the administration of esmolol or normal saline and were repeated after 5, 10, 15, 30 and 45 min. The baseline measurement in both the groups showed that patients were maintaining a state of hyperdynamic circulation with high systolic blood pressure (esmolol group 148 +/- 15 mm Hg, control group 140 +/- 8 mm Hg; p = NS), heart rate (esmolol group 128 +/- 17 bpm, control group 127 +/- 17 bpm; p = NS) and cardiac index (esmolol group 3.1 +/- 1 L/min/m2, control group 3.3 +/- 0.5 L/min/m2; p = NS). Esmolol decreased systolic blood pressure (p < 0.001), heart rate (p < 0.01) and cardiac index (p < 0.05) at five minutes. These changes persisted throughout the study period. The left ventricular stroke work index decreased at five minutes (p < 0.05) and remained so till 30 minutes. The maximum fall in heart rate (15%) and systolic blood pressure (16%) was observed at 45 minutes. There were no haemodynamic changes in the control group except that cardiac index, stroke volume and left ventricular stroke work index increased at five minutes. We conclude that esmolol lowers the indices of cardiovascular work in patients who demonstrated hyperdynamic circulation. This was achieved by decreasing the heart rate and systolic blood pressure which was accompanied by decrease in cardiac index and left ventricular stroke work index.
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Affiliation(s)
- D K Tempe
- Department of Anaesthesiology, GB Pant Hospital, New Delhi
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Williams H, Mehta N. Changes in adult zebra finch song require a forebrain nucleus that is not necessary for song production. J Neurobiol 1999; 39:14-28. [PMID: 10213450] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Male zebra finches normally crystallize song at approximately 90 days and do not show vocal plasticity as adults. However, changes to adult song do occur after unilateral tracheosyringeal (ts) nerve injury, which denervates one side of the vocal organ. We examined the effect of placing bilateral lesions in LMAN (a nucleus required for song development but not for song maintenance in adults) upon the song plasticity that is induced by ts nerve injury in adults. The songs of birds that received bilateral lesions within LMAN followed by right ts nerve injury silenced, on average, 0.25 syllables, and added 0.125 syllables (for an average turnover of 0.375 syllables), and changed neither the frequency with which individual syllables occurred within songs nor the motif types they used most often. In contrast, the songs of birds that received sham lesions followed by ts nerve injury lost, on average, 1.625 syllables, silenced 0.125 syllables, and added 0.75 syllables, turning over an average of 2.5 syllables. They also significantly changed both the frequency with which individual syllables were included in songs and the motif variants used. Thus, song plasticity induced in adult zebra finches with crystallized songs requires the presence of LMAN, a nucleus which had been thought to play a role in vocal production only during song learning. Although the changes to adult songs induced by nerve transection are more limited than those that arise during song development, the same circuitry appears to underlie both types of plasticity.
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Affiliation(s)
- H Williams
- Department of Biology, Williams College, Williamstown, Massachusetts 01267, USA
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Távora MZ, Mehta N, Silva RM, Gondim FA, Hara VM, de Paola AA. Characteristics and identification of sites of chagasic ventricular tachycardia by endocardial mapping. Arq Bras Cardiol 1999; 72:451-74. [PMID: 10531690 DOI: 10.1590/s0066-782x1999000400006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [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: 11/22/2022] Open
Abstract
OBJECTIVE To study electrophysiological characteristics that enable the identification and ablation of sites of chagasic tachycardia. METHODS Thirty-one patients with chronic Chagas' heart disease and sustained ventricular tachycardia (SVT) underwent electrophysiological study to map and ablate that arrhythmia. Fifteen patients had hemodynamically stable SVT reproducible by programmed ventricular stimulation, 9 men and 6 women with ages ranging from 37 to 67 years and ejection fraction varying from 0.17 to 0.64. Endocardial mapping was performed during SVT in all patients. Radiofrequency (RF) current was applied to sites of presystolic activity of at least 30 ms. Entrainment was used to identify reentrant circuits. In both successful and unsuccessful sites of RF current application, electrogram and entrainment were analyzed. RESULTS Entrainment was obtained during all mapped SVT. In 70.5% of the sites we observed concealed entrainment and ventricular tachycardia termination in the first 15 seconds of RF current application. In the unsuccessful sites, significantly earlier electrical activity was seen than in the successful ones. Concealed entrainment was significantly associated with ventricular tachycardia termination. Bystander areas were not observed. CONCLUSION The reentrant mechanism was responsible for the genesis of all tachycardias. In 70.5% of the studied sites, the endocardial participation of the slow conducting zone of reentrant circuits was shown. Concealed entrainment was the main electrophysiological parameter associated with successful RF current application. There was no electrophysiological evidence of bystander regions in the mapped circuits of SVT.
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Affiliation(s)
- M Z Távora
- Universidade Federal de São Paulo-Escola Paulista de Medicina, Brazil
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125
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Richards JM, Gale D, Mehta N, Lestingi T. Combination of chemotherapy with interleukin-2 and interferon alfa for the treatment of metastatic melanoma. J Clin Oncol 1999; 17:651-7. [PMID: 10080611 DOI: 10.1200/jco.1999.17.2.651] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.6] [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: 11/20/2022] Open
Abstract
PURPOSE The primary objective of this clinical study was to assess the feasibility of administering recombinant interleukin-2 and recombinant interferon alfa-2a before and after combination cytotoxic chemotherapy. After encouraging initial responses, the study was expanded to further evaluate the therapeutic potential, clarify the toxicities of this regimen, and explore any associated immunologic changes. PATIENTS AND METHODS Eighty-four patients with metastatic melanoma, including patients with brain metastases, were treated on this 6-week protocol. Patients received combination cisplatin (25 mg/m2/d) and dacarbazine (220 mg/m2/d) on days 1 through 3 and 22 through 24 plus carmustine (150 mg/m2) on day 1. Interleukin 2 (13.5 million IU/m2/d) and interferon alfa (6 MU/m2/d) were administered on days 4 through 8 and 17 through 21. RESULTS Among 83 patients assessable for response, 12 complete and 34 partial responses were documented (55% response rate). The median time to disease progression was 7 months, the median survival from study entry was 12.2 months, and the median survival from diagnosis of metastatic disease was 15.5 months. Although patients were hospitalized to receive treatment, intensive care unit support generally was not needed. Dose-limiting toxicities were related to elevations in serum bilirubin and serum creatinine levels. No patient developed a grade 4 clinical toxicity. Treatment produced a skin depigmentation, which was associated with prolonged survival. CONCLUSION A plateau in both the survival and time to progression curves beyond 2 years (15% of the patients) and a greater than 10% disease-free survival beyond 4 years indicate that there may be a long-term benefit for some patients. The limited toxicity of this regimen should permit its use in most oncology settings. A randomized trial of chemoimmunotherapy versus chemotherapy should be performed to establish the value of chemoimmunotherapy for melanoma.
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Affiliation(s)
- J M Richards
- Department of Medicine, Lutheran General Hospital, Park Ridge, IL 60068, USA
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126
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Butte NF, Hopkinson JM, Mehta N, Moon JK, Smith EO. Adjustments in energy expenditure and substrate utilization during late pregnancy and lactation. Am J Clin Nutr 1999; 69:299-307. [PMID: 9989696 DOI: 10.1093/ajcn/69.2.299] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.0] [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: 11/14/2022] Open
Abstract
BACKGROUND Metabolic adjustments occur during pregnancy and lactation to support fetal growth and milk synthesis; however, the effect of body composition and hormonal milieu on these changes is poorly understood. OBJECTIVE We hypothesized that energy metabolism changes during pregnancy and lactation to support fetal growth and milk synthesis, and that body composition and hormonal milieu influence these alterations. DESIGN We measured energy expenditure, body composition, and hormone, metabolite, and catecholamine concentrations in 76 women (40 lactating, 36 nonlactating) at 37 wk gestation and 3 and 6 mo postpartum. Total energy expenditure (TEE), basal metabolic rate (BMR), sleeping metabolic rate (SMR), and minimal SMR (MSMR) were measured with room calorimetry. Fat-free mass (FFM) and fat mass were estimated with a 4-component model. RESULTS TEE, BMR, SMR, and MSMR were 15-26% higher during pregnancy than postpartum after being adjusted for FFM, fat mass, and energy balance. TEE, SMR, and MSMR were higher in lactating than in nonlactating women. Fasting serum insulin, insulin-like growth factor I, fatty acids, and leptin, and 24-h urinary free norepinephrine, epinephrine, and dopamine correlated positively with TEE, BMR, SMR, and MSMR. In nonlactating women, the respiratory quotient decreased over time, carbohydrate oxidation decreased, and fat oxidation increased. Substrate utilization was not influenced by body composition, fasting serum hormones, or 24-h urinary catecholamines. CONCLUSIONS These results indicate increased energy expenditure and preferential use of carbohydrates during pregnancy and lactation. Elevated respiratory quotient and carbohydrate utilization during pregnancy continue during lactation, consistent with preferential use of glucose by the fetus and mammary gland.
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Affiliation(s)
- N F Butte
- US Department of Agriculture, Agricultural Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.
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127
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Tempe DK, Mehta N, Mohan JC, Tandon MS, Nigam M. Early hemodynamic changes following emergency mitral valve replacement for traumatic mitral insufficiency following balloon mitral valvotomy: report of six cases. Anesthesiology 1998; 89:1583-5. [PMID: 9856740 DOI: 10.1097/00000542-199812000-00043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- D K Tempe
- Department of Anesthesiology, G.B. Pant Hospital, New Delhi, India.
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128
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Bourge R, Eisen H, Hershberger R, Keller A, Radovancevic B, Schreier G, Kastner P, Hutten H, Wery S, Mehta N. Noninvasive rejection monitoring of cardiac transplants using high resolution intramyocardial electrograms: initial US multicenter experience. Pacing Clin Electrophysiol 1998; 21:2338-44. [PMID: 9825344 DOI: 10.1111/j.1540-8159.1998.tb01178.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [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] [Indexed: 11/29/2022]
Abstract
Endomyocardial biopsy (EMB) remains the mainstay for the diagnosis of acute cellular rejection in cardiac transplant patients. A noninvasive alternative that would supplant or reduce the number of EMBs would be a highly desirable and cost-effective tool. To evaluate one potential alternative, a pacemaker with high resolution telemetry capabilities and two fractally coated epimyocardial leads were implanted in 30 patients at five transplant centers during the heart transplant procedure. Ventricular electrograms were recorded during intrinsic and paced activity and digitized to a laptop-based data acquisition device. Electrograms were recorded at frequent intervals and systematically on days when EMBs were performed. The electrogram data were then transferred via the Internet to a central data processing site. Clinical patient management was blinded to the electrogram results and varied considerably among the five centers. Using EMB together with clinical assessment of the transplant revealed 18 cases of clinically significant rejection beyond postoperative day 27 that required antirejection therapy. The normalized parameter values extracted from the electrogram recordings during pacing (the ventricular evoked response) that were associated with significant rejection were statistically lower (86% +/- 16% versus 96% +/- 22%, P < 0.005). The application of a single-threshold diagnosis model to the parameter values allowed detection of significant rejection with a negative predictive value of 98%. This analysis also showed that as many as 55% of the routine surveillance EMBs could have been eliminated had the pacemaker monitoring technique been used as a screening tool prior to EMB. A prospective study should further define the role of this technique in the detection and management of cardiac transplant patients.
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Affiliation(s)
- R Bourge
- University of Alabama at Birmingham, USA
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129
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Grünberg J, Walter J, Eckman C, Capell A, Schindzielorz A, Younkin S, Mehta N, Hardy J, Haass C. Truncated presenilin 2 derived from differentially spliced mRNA does not affect the ratio of amyloid beta-peptide 1-42/1-40. Neuroreport 1998; 9:3293-9. [PMID: 9831466 DOI: 10.1097/00001756-199810050-00027] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [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: 11/25/2022]
Abstract
Numerous mutations in the presenilin (PS) genes cause early onset familial Alzheimer's disease (FAD). Here we characterize the expression of two naturally occurring alternative PS2 transcripts which lack either exons 3 and 4 (PS2 deltaexon3,4) or exons 3, 4, and 8 (PS2 deltaexon3,4,8). These transcripts do not contain the natural initiation codon within exon 3. The transcripts are efficiently translated as N-terminal truncated proteins. These deleted proteins are still able to regulate formation of endogenous PS fragments, indicating that the C-terminal half of the PS2 protein is sufficient for this phenomenon. Although approximately 50% of the PS1 and both PS2 mutations occur within the N-terminal region lacking in the PS2 deltaexon3,4 and PS2 deltaexon3,4,8 proteins, expression of these truncated proteins does not affect pathological generation of amyloid beta-peptide (Abeta). This suggests that point mutations causing AD are gain of function mutations.
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Affiliation(s)
- J Grünberg
- Central Institute of Mental Health, Department of Molecular Biology, Mannheim, Germany
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130
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Mehta N, Hordines J, Sykes D, Doerr RJ, Cohen SA. Low density lipoproteins and Lovastatin modulate the organ-specific transendothelial migration of primary and metastatic human colon adenocarcinoma cell lines in vitro. Clin Exp Metastasis 1998; 16:587-94. [PMID: 9932605 DOI: 10.1023/a:1006548902592] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [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: 11/12/2022]
Abstract
Tumor cell arrest and tumor migration are two of the critical steps in the metastatic cascade. We hypothesized that these steps may be facilitated by the low density lipoprotein (LDL)-induced activation of microvessel endothelial cells (MVEC). The purpose of our study was to investigate the biological effects of an LDL-enriched milieu and the effects of the anticholesterol drug Lovastatin on metastatic behavior. The SW480 and SW620 are primary and metastatic human colonic adenocarcinoma cell lines derived from the same patient. We investigated the effect of LDL on adhesion and migration of the two tumor cell lines across human brain, lung, liver and dermal endothelial monolayers. Adhesion and migration assays were done before and after pretreatment of the MVEC or tumor cells with LDL (100 microg/ml) for 24 h. Although metastatic SW620 cells were more adherent to MVEC compared with primary SW480 cells, LDL pretreatment of SW480 and SW620 cells did not affect tumor cell adhesion to MVEC. In contrast, tumor cell migration was significantly increased across endothelial monolayers when MVEC were pretreated with LDL. Transendothelial cell migration was not significantly affected by pretreatment of the tumor cells with LDL. Lovastatin is an inhibitor of HMG-CoA reductase, the rate-limiting enzyme in cholesterol biosynthesis. It has been shown to have anti-tumor activity in vitro. We investigated the effect of Lovastatin on tumor cell kinetics and tumor cell migration across MVEC. Growth curves and migration assays were done before and after pretreatment of the tumor cells with Lovastatin (30 microg/ml). Migration assays were also done after treatment of unstimulated or LDL-stimulated MVEC (100 microg/ml) for 24 h with Lovastatin. Lovastatin inhibited the in vitro growth of the metastatic SW620 cell line to a greater extent than the invasive SW480E cell line. On the other hand, pretreatment of tumor cells with Lovastatin (30 microg/ml) did not suppress transendothelial tumor cell migration of tumor cells. Finally, Lovastatin given to mice effectively suppressed the number of MCA-26 tumor colonies in the liver of Balb/c mice compared with untreated mice.
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Affiliation(s)
- N Mehta
- VA Medical Center, Department of Surgery, School of Medicine, State University of New York at Buffalo, 14215, USA
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131
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Agrawal D, Lohchab SS, Mehta N, Bohra P, Bhargava M, Bhardwaj S, Tempe D, Khanna SK. Coronary sinus rupture secondary to retrograde cardioplegia. Indian Heart J 1998; 50:542-4. [PMID: 10052282] [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: 02/11/2023] Open
Affiliation(s)
- D Agrawal
- Department of Cardiothoracic Surgery, GB Pant Hospital, New Delhi
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132
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Abstract
Congenital tuberculosis is a rare disease. The non-specific nature of presenting signs and symptoms (because of the lack of host response) and the fatal outcome in the absence of early therapy all underscore the importance of early diagnosis and treatment in infants. Recognition requires awareness that tuberculosis at this age has manifestations not found in older children. Here a case of congenital tuberculosis is presented, where changes were confined only to the thorax. Tuberculosis in the mother could be diagnosed only retrospectively.
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Affiliation(s)
- M B Popli
- Department of Radiological Imaging, Maulana Azad Medical College and Associated Hospitals, Delhi, India
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133
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Brenner RA, Simons-Morton BG, Bhaskar B, Mehta N, Melnick VL, Revenis M, Berendes HW, Clemens JD. Prevalence and predictors of the prone sleep position among inner-city infants. JAMA 1998; 280:341-6. [PMID: 9686551 DOI: 10.1001/jama.280.4.341] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT The prone sleep position is associated with an increased risk of sudden infant death syndrome (SIDS), but few studies have assessed factors associated with the choice of infant sleep position. OBJECTIVES To describe infant sleep position in a cohort of infants born to predominantly low-income, inner-city mothers and to identify predictors of the prone sleep position in this population. DESIGN Prospective birth cohort study. PATIENTS AND SETTING Three hundred ninety-four mother-infant dyads, systematically selected from 3 District of Columbia hospitals between August 1995 and September 1996. Mothers were interviewed shortly after delivery and again at 3 to 7 months postpartum. MAIN OUTCOME MEASURES Position in which infants were placed for sleep on the night prior to the 3- to 7-month interview. RESULTS At 3 to 7 months of age, 157 infants (40%) were placed for sleep in the prone position. Independent predictors of prone sleep position included poverty (odds ratio [OR], 1.81; 95% confidence interval [CI], 1.10-2.99), black race (OR, 2.06; 95% CI, 1.05-4.04), presence of infant's grandmother in the home (OR, 1.83; 95% CI, 1.11-3.00), and intent, as measured shortly after delivery, to place the infant in the prone position (OR, 2.28; 95% CI, 1.44-3.60). Importantly, of the 43 mothers who observed their infants in the prone sleep position while in the hospital, 40 (93%) intended to place their infants prone at home. CONCLUSIONS A substantial proportion of infants in this predominantly low-income population were placed in the prone sleep position. Educational efforts should address both initial intentions and reinforcement of the correct sleep position, once initiated. Hospitals should ensure that healthy newborn infants are placed in the supine sleep position during the postpartum hospital stay.
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Affiliation(s)
- R A Brenner
- Division of Epidemiology, Statistics, and Prevention Research, National Institute of Child Health and Human Development, Bethesda, MD 20892, USA.
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Tempe DK, Mehta N, Mohan JC, Tandon MS, Nigam M. Emergency mitral valve replacement for traumatic mitral insufficiency following balloon mitral valvotomy: an early haemodynamic study. Ann Card Anaesth 1998; 1:49-55. [PMID: 17846466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023] Open
Abstract
Acute severe mitral insufficiency may occur during percutaneous transvenous balloon mitarl valvotomy. Urgent surgical intervention in the form of mitral valve repair or replacement may be necessary in these patients. The haemodynamic measurements at various stages in these patients were obtained and compared with those of patients undergoing elective mitral valve replacement for chronic mitral regurgitation. Between September 1995 and December 1947, urgent mitral valve replacement was performed in 14 patients out of a total of 1688 patients who underwent balloon mitral valvotomy. Haemodynamic measurements could be obtained in 7 of these patients and they constituted group I. Eight other patients undergoing elective mitral valve replacement during the same period for chronic mitral regurgitation constituted group II. Standard haemodynamic measurements were obtained at the following stages: (1) Baseline- 20-30 min after endotracheal intubation; (2) stage 1- 20-30 min after termination of the cardiopulmonary bypass: (3) stage 2- four hours after the patient was transferred to ICU and (4) stage 3-30 min after extubation. All the patients were suffering from severe pulmonary hypertension. However, the indices of pulmonary artery hypertension such as mean pulmonary artery pressure, pulmonary capillary wedge pressure, pulmonary vascular resistance as well as right ventricular systolic and end-diastolic pressures did not decrease after surgery in group I. In contrast, in group II, there was significant decrease in mean pulmonary artery pressure (p<0.05), pulmonary capillary wedge pressure (p<0.05), right ventricular systolic (p<0.001) and end-diastolic pressures (p<0.05) at stage 1. These changes persisted throughout the study period. Pulmonary vascular resistance showed a decreasing trend, but attained statistical significance at stage 1 only. Two patients died; one of intractable cardiac failure and another from septicaemia and multiple organ failure in group I, but there were no deaths in group II. Reactive pulmonary hypertension secondary to acute mitral regurgitation may not recover immediately following mitral valve replacement and may be responsible for poor outcome in these patients.
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Affiliation(s)
- D K Tempe
- Departments of Anaesthesiology, Cardiac Surgery and Cardiology, GB Pant Hospital, New Delhi, India
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135
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Agrawal D, Lohchab SS, Mehta N, Bhargava M, Panwar S, Bhardwaj S, Dubey S, Satsangi DK, Banerjee A, Nigam M, Khanna SK. Post-cardiotomy intra-aortic balloon counter pulsation: application and prognostic evaluation. Indian Heart J 1998; 50:313-7. [PMID: 9753854] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Cardiac assistance by intra-aortic balloon counter pulsation was studied in 113 cardiac surgical cases comprising 91 male and 22 female patients. This included 82 percent of patients having coronary artery bypass surgery, while 18 percent were operated for valvular lesions. It was observed that the time of institution of cardiac assistance by intra-aortic balloon counter pulsation, following cardiac surgery, was of prime importance to decrease patient mortality. It was lowest (16%) when the balloon was inserted for assistance before termination and highest (50%) when there was delay of more than 15 minutes following termination of cardiopulmonary bypass. Early balloon assistance significantly lowered the pulmonary capillary wedge pressure and usually 1:2 augmentation was more effective, probably because of existing tachycardia in most patients. Advances in catheter technology have reduced the vascular complication at the insertion site. Percutaneous insertion had less local complications (13.3%) than open arteriotomy technique (31.2%). Similarly with sheathless insertion, complications were less (6.6%) in comparison to sheathed insertion (21.7%). Proper placement of balloon avoided position-related complications and there was no compromise of blood flow through left internal mammary artery as noticed in our series.
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Affiliation(s)
- D Agrawal
- Department of Cardiothoracic Surgery, GB Pant Hospital, New Delhi
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136
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Pennypacker KR, Fuldner R, Xu R, Hernandez H, Dawbarn D, Mehta N, Perez-Tur J, Baker M, Hutton M. Cloning and characterization of the presenilin-2 gene promoter. Brain Res Mol Brain Res 1998; 56:57-65. [PMID: 9602061 DOI: 10.1016/s0169-328x(98)00028-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Mutations in the presenilin-2 (PS-2) have been shown to cause early onset Alzheimer's disease (AD) in a series of families known as the Volga Germans and in an unrelated Italian kindred. Expression of the PS-2 gene is regulated during AD, aging, development and brain injury. Although expressed primarily in neurons, enhanced levels of PS-2 have been reported in astrocytes activated by neuronal damage. Understanding the regulation of the PS-2 gene may thus provide an insight into its role in AD. We have isolated a 3635 bp DNA fragment that contains 2934 bp of DNA sequence upstream from the PS-2 gene. Primer extension analysis was used to map three major transcriptional start sites within the PS-2 gene. The promoter sequence, upstream of each transcriptional start site, does not contain TATA or CAAT boxes but does contain several GC rich sites (Sp-1 and AP-2). A reporter gene construct containing the PS-2 promoter (PS2P, -2934 to +702) transfected into M17 cells drives basal transcription to 20% of the levels of the SV-40 viral promoter. Addition of NGF to PC-12 cells was found to upregulate the PS2P promoter and an NGF-responsive element was localized by deletional analysis between -403 and +13 within the promoter. Since the PS-2 gene has multiple start sites and the upstream sequence is GC rich with no TATA box, the PS-2 promoter is consistent with the GC class of 'housekeeping' genes.
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Affiliation(s)
- K R Pennypacker
- Department of Pharmacology and Therapeutics, University of South Florida, Tampa, FL 33612, USA
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137
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Crook R, Verkkoniemi A, Perez-Tur J, Mehta N, Baker M, Houlden H, Farrer M, Hutton M, Lincoln S, Hardy J, Gwinn K, Somer M, Paetau A, Kalimo H, Ylikoski R, Pöyhönen M, Kucera S, Haltia M. A variant of Alzheimer's disease with spastic paraparesis and unusual plaques due to deletion of exon 9 of presenilin 1. Nat Med 1998; 4:452-5. [PMID: 9546792 DOI: 10.1038/nm0498-452] [Citation(s) in RCA: 238] [Impact Index Per Article: 9.2] [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: 02/07/2023]
Abstract
We describe a novel variant of Alzheimer's disease (AD) in a Finnish pedigree with 17 affected individuals of both sexes in three generations. The disease is characterized by progressive dementia which is, in most cases, preceded by spastic paraparesis. Neuropathological investigations revealed numerous, distinct, large, round and eosinophilic plaques as well as neurofibrillary tangles and amyloid angiopathy throughout the cerebral cortex. The predominant plaques resembled cotton wool balls and were immunoreactive for Abeta but lacked a congophilic dense core or marked plaque-related neuritic pathology. Molecular genetic analysis revealed that the disease was caused by a deletion of exon 9 (delta9) of the presenilin 1 (PS1) gene from the mRNA: unlike previous examples of the delta9 variant, the deletion was not caused by a splice acceptor site mutation.
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Affiliation(s)
- R Crook
- Mayo Clinic Jacksonville, Florida 32084, USA
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138
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Abstract
Knotting of a balloon-tipped, flow-directed catheter leading to difficulty in its removal is a rare but serious complication. Several methods have been used to remove such catheters with nonsurgical techniques. A case of knotted catheter that was also entrapped in a surgical suture in a patient undergoing emergency mitral valve replacement is presented and a method for its nonsurgical removal is described.
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Affiliation(s)
- N Mehta
- Department of Anaesthesiology, GB Pant Hospital, New Delhi, India
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139
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Tempe DK, Mehta N, Mishra B, Tondon MS, Tomar AS, Budharaja P, Nigam M. Bacteriological Profile of Patients Undergoing Open Heart Surgery and Evaluation of a Bacterial Filter using Protected Broncho-Alveolar Lavage. Ann Card Anaesth 1998; 1:23-30. [PMID: 17827620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023] Open
Abstract
Twenty seven patients undergoing elective open heart surgery were included in this prospective study. They were randomly divided into two groups. Group C (n = 12) constituted the control group in whom no breathing filter was used in the anaesthesia circuit in the operating room or in the ICU. Humidification of breathing gases was achieved with the help of conventional heated humidifier. In group F (n = 15), heat and moisture exahanging bacterial / viral filter was incorporated in the breathing circuit at the patient end between the catheter mount and Y connection of the breathing circuit. In both the groups, samples of throat swab, protected broncho-alveolar lavage with double catheter and Ryles tube aspirate were collected preoperatively (in the operation theatre) and postoperatively (in the Intensive Care Unit on day 1). All the samples were sent to the laboratory immediately after the collection for Gram staining and culture and sensitivity. Pathogenic organisms were isolated from a total of 9 patients (33%) preoperatively. Exogenous spread of the organisms to the lungs was considered to have occurred if new pathogenic organisms were isolated from the postoperative bronchoalveolar lavage and the simultaneous samples of the throat swab and Ryles tube did not contain the same organism. By this definition, the exogenous spread of the organisms occurred in one patient in group C and in no patient in group F (P = 0.46, Fishers test). The commonest organisms isolated were Staphylococcus aureus, Klebsiella sp. and Pseudomonas sp. We conclude that colonization of the pathogenic organisms is common (33%) in orophrynx and gastrointestinal tract in hospitalized patients. There was no difference in the exogenous spread of the organisms between the two groups. The unity of the filter, therefore, appears to be limited to prevent contamination of anaesthesia machines or ventilators as has been shown by earlier studies.
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Affiliation(s)
- D K Tempe
- Departments of Anaesthesiology and Microbiology, G.B.Pant Hospital, New Delhi, India
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140
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Chakraborti KL, Ku S, Tripathi RP, Mehta N. Conventional and magnetic resonance angiographic evaluation of cirsoid aneurysm. Neurol India 1998; 46:44-47. [PMID: 29504595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Cirsoid aneurysms are considered to be notoriously difficult lesions. A proper diagnostic evaluation is essential for the successful management of these lesions. The authors present here both conventional and magnetic resonance angiographic appearance of six cases of cirsoid aneurysms. Four of these had congenital and two had post traumatic cirsoid aneurysms. Only two out of the six patients were evaluated by magnetic resonance angiography, while all the six patients underwent conventional angiography. Though magnetic resonance angiography described the feeders of the malformation well, it could not define the draining veins satisfactorily. On the contrary, conventional angiography described both feeding arteries and the venous drainage.
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Affiliation(s)
- K L Chakraborti
- Department of Neurosurgery, G.B.Pant Hospital and NMR Research Division, New Delhi - 110 054, India
| | - S Ku
- Department of Neurosurgery, G.B.Pant Hospital and NMR Research Division, New Delhi - 110 054, India
| | - R P Tripathi
- Department of Neurosurgery, G.B.Pant Hospital and NMR Research Division, New Delhi - 110 054, India
| | - N Mehta
- Department of Neurosurgery, G.B.Pant Hospital and NMR Research Division, New Delhi - 110 054, India
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141
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Mehta N, Hordines J, Volpe C, Doerr R, Cohen SA. Cellular effects of hypercholesterolemia in modulation of cancer growth and metastasis: a review of the evidence. Surg Oncol 1997; 6:179-85. [PMID: 9576633 DOI: 10.1016/s0960-7404(97)00027-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [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: 02/07/2023]
Abstract
Hypercholesterolemia and increased cancer risk have been associated, particularly with the high fat diets characteristic of Western societies. We were interested in the possible association between preexisting hypercholesterolemia and the rapidity and extent of tumor metastases in these patients. To date there has been only a few studies that have suggested and explored this determinant of cancer metastases although it may play a role in a subset of patients who develop cancers. This article will review the literature on the effects of LDL-cholesterol on cell proliferation and differentiation and speculate on mechanisms of involvement of a hypercholesterolemic milieu on cancer progression and enhancement of metastatic potential.
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Affiliation(s)
- N Mehta
- Department of Surgery, VA Medical Center, State University of New York at Buffalo, 14215, USA
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142
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Williams JC, Gharbia SE, Gulabivala K, Rajendram D, Mehta N, Huttson R, Collins MD, Shah HN. Noncultivable microbial communities in dentine and cementum: a molecular analytical approach. Clin Infect Dis 1997; 25 Suppl 2:S233-4. [PMID: 9310689 DOI: 10.1086/516203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Affiliation(s)
- J C Williams
- Eastman Dental Institute, University of London, United Kingdom
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143
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Abstract
Absorption and degradation of metalaxyl were studied in mustard (Brassica juncea) plants after application as a seed dresser, a foliar spray, and a combination of both under subtropical conditions in India. Results indicated that absorption of metalaxyl increased up to 30 days when it was applied as a seed dresser; thereafter, it started declining and was not detectable after 60 days of sowing. The maximum residues (average, 9.03 ppm) of metalaxyl were found after 1 day of spraying. The dissipation of metalaxyl after initial deposits on mustard plants was almost complete after 15 days of spraying. The safe waiting period of metalaxyl was calculated to be 62 and 8 days for seed dresser and foliar application, respectively. The seeds raised through treatments under study were completely free from any detectable amount of metalaxyl residues.
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Affiliation(s)
- N Mehta
- Department of Plant Pathology, CCS Haryana Agricultural University, Hisar, India
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144
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Abstract
BACKGROUND Although standard formulas for preterm infants promote intrauterine rates of weight gain, fat deposition in preterm infants fed these formulas has been reported to be considerably higher than that in the fetus. We hypothesized that a preterm infant formula with a higher protein:energy (P:E) ratio would promote accretion rates of fat, fat-free mass, and minerals closer to those of the fetus. METHODS As part of a larger study to determine whether accretion rates of fat and fat-free mass closer to those of the fetus can be achieved with a higher P:E ratio, we present a descriptive analysis of 72-h nutrient balance studies performed on a subset (n = 15/30) of the infants randomly assigned to be fed formula with a P:E ratio of either 3.2 g/100 kcal or 2.6 g/100 kcal. RESULTS Despite the higher intake and net absorption of nitrogen by infants fed the higher P:E formula, there was no statistically significant difference in net nitrogen retention between groups. There also were no statistically significant differences between groups in digestible energy, metabolizable energy, energy expenditure, or energy storage. Thus, partitioning of stored energy as protein and fat did not differ between groups. The retention of calcium, phosphorus, sodium, potassium, copper, and zinc also did not differ between groups, and nitrogen intake did not affect mineral retention. CONCLUSIONS In this study, formula for preterm infants with a P:E ratio of 3.2 g/100 kcal vs. 2.6 g/100 kcal provided no apparent benefit in terms of the proportion of fat to lean tissue accretion as determined from nutrient balance data.
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Affiliation(s)
- A K Fairey
- Southern Mississippi Neonatology, Hattiesburg, USA
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145
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Agrawal D, Dubey S, Saket B, Bhargava M, Mehta N, Lohchab SS, Satsangi DK, Nigam M, Gupta BK, Khanna SK. Thrombolytic therapy for prosthetic valve thrombosis in Third World countries. Indian Heart J 1997; 49:383-6. [PMID: 9358660] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
In order to clarify the role of thrombolytic therapy for treatment of prosthetic valve thrombosis, all cases admitted in the intensive care unit (ICU), between March 1987 and March 1997 with the diagnosis of prosthetic valve thrombosis and treated with streptokinase, were analysed. In total, 42 patients with clinical and echocardiographic evidence of left side tilting disc prosthetic valve thrombosis were treated. All the patients had only mitral valve prosthesis involvement. Streptokinase was administered as a bolus of 2.5 lac units over 30 minutes followed by 1 lac units/hour for 48-72 hours. Thirty-seven (88%) patients had successful thrombolysis. Overall mortality occurred in 9.5 percent patients due to systemic embolism and bleeding complications. Serial clinical, radiological and echocardiographic studies showed successful thrombolysis in 88 percent patients. This study demonstrates that streptokinase therapy is safe and effective first line treatment for left-sided prosthetic valve thrombosis and surgery should be reserved for those patients who fail to respond to thrombolytic therapy.
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Affiliation(s)
- D Agrawal
- Department of Cardiothoracic Surgery and Cardiology, GB Pant Hospital, New Delhi
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146
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Hébert P, Mehta N, Wang J, Hindmarsh T, Jones G, Cardinal P. Functional magnesium deficiency in critically ill patients identified using a magnesium-loading test. Crit Care Med 1997; 25:749-55. [PMID: 9187591 DOI: 10.1097/00003246-199705000-00007] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.7] [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: 02/04/2023]
Abstract
OBJECTIVE To determine the feasibility of the magnesium-loading test in the critically ill and to validate serum ionized magnesium assay using the magnesium-loading test as a reference in this same patient population. DESIGN Double-blind, randomized, controlled clinical investigation. SETTING Tertiary level intensive care unit. PATIENTS Forty-four consecutive critically ill patients without evidence of renal insufficiency. INTERVENTION Patients were randomly allocated to receive 30 mmol (7.5 g) of magnesium sulfate daily for 3 days, or an equivalent amount of normal saline. MEASUREMENTS AND MAIN RESULTS We recorded baseline characteristics, and serial serum biochemical measurements included creatinine, glucose, sodium, potassium, phosphate, total calcium, ionized calcium, total magnesium, and ionized magnesium. Serum assays were accompanied by 24-hr urine collections of creatinine and magnesium over the 3-day period. Baseline characteristics were comparable in both groups. In patients receiving magnesium, serum ionized magnesium and total magnesium concentrations were increased by 43% (p = .0001) and 59% (p = .0002), respectively, on day 1 as compared with the control group. Magnesium excretion in the control group averaged 4.8 +/- 2.3 mmol/day during the 3-day study period, while the magnesium excretion in the magnesium-loaded group was significantly increased to 22.7 +/- 10.9 mmol/day (p < .0001). Following day 1 magnesium loading, patients who excreted < 70% of the total magnesium (30 mmol infused magnesium plus 4.8 mmol basal excretion) were termed as functionally magnesium-deficient retainers (n = 12), and patients who excreted > 70% of the total magnesium were termed as nonretainers (n = 7). In addition, magnesium retainers on day 2 (nine of ten patients) and day 3 (five of six patients) excreted > 70% of the total magnesium, indicating a replenishment of body magnesium stores. In contrast, nonretainers on day 2 (four of five patients), and day 3 (four of four patients) continued to excrete excess amounts of magnesium. In the retainer group, only two patients had a low serum ionized magnesium concentration, while two other patients had low total serum magnesium values. In addition, magnesium retention was associated with low ionized calcium and high phosphate values. CONCLUSIONS The magnesium-loading test is feasible and appears to be valid based on its performance during the 3-day evaluation. Using the magnesium-loading test as a reference, serum ionized magnesium appears to be an insensitive biochemical marker of functional hypomagnesemia. Larger cohort studies using the magnesium-loading test will help establish the true prevalence of magnesium deficiency and its associated risk factors in critically ill patients.
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Affiliation(s)
- P Hébert
- Department of Pathology, Ottawa General Hospital, University of Ottawa, ON, Canada
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147
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Groblewski GE, Grady T, Mehta N, Lambert H, Logsdon CD, Landry J, Williams JA. Cholecystokinin stimulates heat shock protein 27 phosphorylation in rat pancreas both in vivo and in vitro. Gastroenterology 1997; 112:1354-61. [PMID: 9098021 DOI: 10.1016/s0016-5085(97)70149-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND & AIMS Mammalian heat shock protein 27 (hsp27) is believed to function under normal physiological conditions and during cellular stress. Recent studies indicate a role for hsp27 in regulating actin-cytoskeletal dynamics. In the present study, secretagogue-regulated phosphorylation of hsp27 in rat exocrine pancreas was investigated both in vivo and in isolated acinar cells. METHODS Western analysis after two-dimensional electrophoresis was used to measure the phosphorylation of hsp27 after treatment of rats or acinar cells with secretagogues. Cholecystokinin-stimulated mitogen-activated protein kinase-activated protein (MAPKAP) kinase 2 activity was measured after immunoprecipitation of the kinase. RESULTS hsp27 exists as three isoforms in acini: one nonphosphorylated (pI 6.2) and two phosphorylated (pIs 5.9 and 5.7) forms. Infusion of rats with a secretory or supermaximal dose of cerulein produced an acidic shift in hsp27, indicating an increase in its phosphorylation; the higher dose, known to cause pancreatitis, had a twofold greater effect. In isolated acini, increases in hsp27 phosphorylation were evident at 10 pmol/L and maximal at 1 nmol/L cholecystokinin. The hsp27-specific kinase MAPKAP kinase 2 was activated 2.4-fold with 1 nmol/L cholecystokinin treatment. CONCLUSIONS hsp27 phosphorylation was stimulated by low and high concentrations of cholecystokinin, both in vivo and in vitro. Phosphorylation was potentially mediated via the MAPKAP kinase 2 intracellular signaling pathway.
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Affiliation(s)
- G E Groblewski
- Department of Physiology, University of Michigan Medical School, Ann Arbor 48109-0622, USA
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148
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Tempe DK, Joshi N, Mehta N, Khanna SK, Banerjee A, Tyagi S. Anaesthetic management of patients undergoing surgery for tachyarrhythmias. Initial experience with 16 patients. Indian Heart J 1997; 49:173-8. [PMID: 9231550] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Sixteen patients suffering from various cardiac arrhythmias were treated surgically. Intraoperative computerised electrophysiologic mapping was used in 14. Thirteen patients were suffering from Wolff-Parkinson-White syndrome. They underwent surgical division or cryoablation of accessory pathways. Two patients who had rheumatic mitral stenosis with left atrial clot underwent "Maze III" procedure with open mitral commissurotomy and clot removal. One patient with paroxysmal refractory ventricular tachycardia and a left ventricular aneurysm had an aneurysmectomy with subendocardial resection of the arrhythmic focus. All antiarrhythmic medications were discontinued preoperatively. Morphine was the principal anaesthetic agent, supplemented with halothane. Muscle relaxation was provided with pancuronium bromide. The various problems encountered included hypotension and arrhythmia during placement of epicardial band array for mapping (4 patients), ventricular tachycardia during internal jugular vein cannulation (1 patient) and continuance of delta wave after cryoablation in 2 patients. Halothane may have interfered with electrophysiologic mapping and accurate localization of accessory pathway leading to persistence of delta wave. The choice of anaesthetic agents should be guided by the electrophysiologic effects and potential influence of these agents on the accessory pathways.
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Affiliation(s)
- D K Tempe
- Department of Anaesthesiology, GB Pant Hospital, New Delhi
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149
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Ukani M, Nanavati D, Mehta N. A review on the ayurvedic herb tribulus terrestris L. Anc Sci Life 1997; 17:144-50. [PMID: 22556836 PMCID: PMC3331096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/1996] [Accepted: 01/27/1997] [Indexed: 11/05/2022] Open
Abstract
Gokhshura (Tribulus Linn) of Family Zygophyllaceae is an indigenous plant which has been mentioned in Ayurveda with several clinical properties. The plant finds use in one form or the other in various ayurvedic preparations and this has been made it necessary to review the various studies carried out in its chemistry as well as pharmacology.
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Affiliation(s)
- M.D. Ukani
- BAN LABS Pvt. Ltd., Dr. Vikram Sarabhai Nagar, Gondal Road (South), Rajkot – 360 004, Gujarat, India
| | - D.D. Nanavati
- BAN LABS Pvt. Ltd., Dr. Vikram Sarabhai Nagar, Gondal Road (South), Rajkot – 360 004, Gujarat, India
| | - N.K. Mehta
- BAN LABS Pvt. Ltd., Dr. Vikram Sarabhai Nagar, Gondal Road (South), Rajkot – 360 004, Gujarat, India
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150
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Abstract
Ganglioneuroblastoma is an unusual tumour in an adult. We present a case of bilateral intraabdominal ganglioneuroblastoma in an adult patient. The two tumours had different morphological features and origins. The appearances on ultrasound, CT and MRI are discussed. To the best of our knowledge, this is the first case of bilateral ganglioneuroblastoma reported in an adult patient with ultrasound, CT and MRI findings.
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Affiliation(s)
- N Mehta
- Imaging Division, Institute of Nuclear Medicine and Allied Sciences, Delhi, India
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