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Bloom SI, Tucker JR, Machin DR, Abdeahad H, Adeyemo AO, Thomas TG, Bramwell RC, Lesniewski LA, Donato AJ. Reduction of double-strand DNA break repair exacerbates vascular aging. Aging (Albany NY) 2023; 15:9913-9947. [PMID: 37787989 PMCID: PMC10599741 DOI: 10.18632/aging.205066] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 08/28/2023] [Indexed: 10/04/2023]
Abstract
Advanced age is the greatest risk factor for cardiovascular disease (CVD), the leading cause of death. Arterial function is impaired in advanced age which contributes to the development of CVD. One underexplored hypothesis is that DNA damage within arteries leads to this dysfunction, yet evidence demonstrating the incidence and physiological consequences of DNA damage in arteries, and in particular, in the microvasculature, in advanced age is limited. In the present study, we began by assessing the abundance of DNA damage in human and mouse lung microvascular endothelial cells and found that aging increases the percentage of cells with DNA damage. To explore the physiological consequences of increases in arterial DNA damage, we evaluated measures of endothelial function, microvascular and glycocalyx properties, and arterial stiffness in mice that were lacking or heterozygous for the double-strand DNA break repair protein ATM kinase. Surprisingly, in young mice, vascular function remained unchanged which led us to rationalize that perhaps aging is required to accumulate DNA damage. Indeed, in comparison to wild type littermate controls, mice heterozygous for ATM that were aged to ~18 mo (Old ATM +/-) displayed an accelerated vascular aging phenotype characterized by increases in arterial DNA damage, senescence signaling, and impairments in endothelium-dependent dilation due to elevated oxidative stress. Furthermore, old ATM +/- mice had reduced microvascular density and glycocalyx thickness as well as increased arterial stiffness. Collectively, these data demonstrate that DNA damage that accumulates in arteries in advanced age contributes to arterial dysfunction that is known to drive CVD.
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Affiliation(s)
- Samuel I. Bloom
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT 84148, USA
| | - Jordan R. Tucker
- Department of Internal Medicine, Division of Geriatrics, University of Utah School of Medicine, Salt Lake City, UT 84148, USA
| | - Daniel R. Machin
- Department of Nutrition and Integrative Physiology, Florida State University, Tallahassee, FL 32304, USA
| | - Hossein Abdeahad
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT 84148, USA
| | - AdeLola O. Adeyemo
- Department of Internal Medicine, Division of Geriatrics, University of Utah School of Medicine, Salt Lake City, UT 84148, USA
| | - Tyler G. Thomas
- Department of Internal Medicine, Division of Geriatrics, University of Utah School of Medicine, Salt Lake City, UT 84148, USA
| | - R. Colton Bramwell
- Department of Internal Medicine, Division of Geriatrics, University of Utah School of Medicine, Salt Lake City, UT 84148, USA
| | - Lisa A. Lesniewski
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT 84148, USA
- Department of Internal Medicine, Division of Geriatrics, University of Utah School of Medicine, Salt Lake City, UT 84148, USA
- Geriatric Research, Education and Clinical Center, Veteran’s Affairs Medical Center-Salt Lake City, Salt Lake City, UT 84148, USA
- Nora Eccles Harrison Cardiovascular Research and Training Institute, The University of Utah, Salt Lake City, UT 84148, USA
| | - Anthony J. Donato
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT 84148, USA
- Department of Internal Medicine, Division of Geriatrics, University of Utah School of Medicine, Salt Lake City, UT 84148, USA
- Geriatric Research, Education and Clinical Center, Veteran’s Affairs Medical Center-Salt Lake City, Salt Lake City, UT 84148, USA
- Nora Eccles Harrison Cardiovascular Research and Training Institute, The University of Utah, Salt Lake City, UT 84148, USA
- Department of Biochemistry, University of Utah, Salt Lake City, UT 84148, USA
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Bloom SI, Liu Y, Tucker JR, Islam MT, Machin DR, Abdeahad H, Thomas TG, Bramwell RC, Lesniewski LA, Donato AJ. Endothelial cell telomere dysfunction induces senescence and results in vascular and metabolic impairments. Aging Cell 2023; 22:e13875. [PMID: 37259606 PMCID: PMC10410008 DOI: 10.1111/acel.13875] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 04/03/2023] [Accepted: 05/04/2023] [Indexed: 06/02/2023] Open
Abstract
In advanced age, increases in oxidative stress and inflammation impair endothelial function, which contributes to the development of cardiovascular disease (CVD). One plausible source of this oxidative stress and inflammation is an increase in the abundance of senescent endothelial cells. Cellular senescence is a cell cycle arrest that occurs in response to various damaging stimuli. In the present study, we tested the hypothesis that advanced age results in endothelial cell telomere dysfunction that induces senescence. In both human and mouse endothelial cells, advanced age resulted in an increased abundance of dysfunctional telomeres, characterized by activation of DNA damage signaling at telomeric DNA. To test whether this results in senescence, we selectively reduced the telomere shelterin protein telomere repeat binding factor 2 (Trf2) from endothelial cells of young mice. Trf2 reduction increased endothelial cell telomere dysfunction and resulted in cellular senescence. Furthermore, induction of endothelial cell telomere dysfunction increased inflammatory signaling and oxidative stress, resulting in impairments in endothelial function. Finally, we demonstrate that endothelial cell telomere dysfunction-induced senescence impairs glucose tolerance. This likely occurs through increases in inflammatory signaling in the liver and adipose tissue, as well as reductions in microvascular density and vasodilation to metabolic stimuli. Cumulatively, the findings of the present study identify age-related telomere dysfunction as a mechanism that leads to endothelial cell senescence. Furthermore, these data provide compelling evidence that senescent endothelial cells contribute to age-related increases in oxidative stress and inflammation that impair arterial and metabolic function.
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Affiliation(s)
- Samuel I. Bloom
- Department of Nutrition and Integrative PhysiologyThe University of UtahSalt Lake CityUtahUSA
| | - Yu Liu
- Department of GeriatricsTongji HospitalWuhanChina
- Division of Geriatrics, Department of Internal MedicineUniversity of Utah School of MedicineSalt Lake CityUtahUSA
| | - Jordan R. Tucker
- Division of Geriatrics, Department of Internal MedicineUniversity of Utah School of MedicineSalt Lake CityUtahUSA
| | - Md Torikul Islam
- Department of Nutrition and Integrative PhysiologyThe University of UtahSalt Lake CityUtahUSA
| | - Daniel R. Machin
- Division of Geriatrics, Department of Internal MedicineUniversity of Utah School of MedicineSalt Lake CityUtahUSA
- Department of Nutrition and Integrative PhysiologyFlorida State UniversityTallahasseeFloridaUSA
| | - Hossein Abdeahad
- Department of Nutrition and Integrative PhysiologyThe University of UtahSalt Lake CityUtahUSA
| | - Tyler G. Thomas
- Division of Geriatrics, Department of Internal MedicineUniversity of Utah School of MedicineSalt Lake CityUtahUSA
| | - R. Colton Bramwell
- Division of Geriatrics, Department of Internal MedicineUniversity of Utah School of MedicineSalt Lake CityUtahUSA
| | - Lisa A. Lesniewski
- Department of Nutrition and Integrative PhysiologyThe University of UtahSalt Lake CityUtahUSA
- Division of Geriatrics, Department of Internal MedicineUniversity of Utah School of MedicineSalt Lake CityUtahUSA
- Geriatric Research, Education and Clinical CenterVeteran's Affairs Medical Center‐Salt Lake CitySalt Lake CityUtahUSA
- Nora Eccles Harrison Cardiovascular Research and Training InstituteThe University of UtahSalt Lake CityUtahUSA
| | - Anthony J. Donato
- Department of Nutrition and Integrative PhysiologyThe University of UtahSalt Lake CityUtahUSA
- Division of Geriatrics, Department of Internal MedicineUniversity of Utah School of MedicineSalt Lake CityUtahUSA
- Geriatric Research, Education and Clinical CenterVeteran's Affairs Medical Center‐Salt Lake CitySalt Lake CityUtahUSA
- Nora Eccles Harrison Cardiovascular Research and Training InstituteThe University of UtahSalt Lake CityUtahUSA
- Department of BiochemistryThe University of UtahSalt Lake CityUtahUSA
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Bloom SI, Tucker JR, Lim J, Thomas TG, Stoddard GJ, Lesniewski LA, Donato AJ. Aging results in DNA damage and telomere dysfunction that is greater in endothelial versus vascular smooth muscle cells and is exacerbated in atheroprone regions. GeroScience 2022; 44:2741-2755. [PMID: 36350415 PMCID: PMC9768045 DOI: 10.1007/s11357-022-00681-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 10/26/2022] [Indexed: 11/11/2022] Open
Abstract
Aging increases the risk of atherosclerotic cardiovascular disease which is associated with arterial senescence; however, the mechanisms responsible for the development of cellular senescence in endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) remain elusive. Here, we study the effect of aging on arterial DNA damage and telomere dysfunction. Aging resulted in greater DNA damage in ECs than VSMCs. Further, telomere dysfunction-associated DNA damage foci (TAF: DNA damage signaling at telomeres) were elevated with aging in ECs but not VMSCs. Telomere length was modestly reduced in ECs with aging and not sufficient to induce telomere dysfunction. DNA damage and telomere dysfunction were greatest in atheroprone regions (aortic minor arch) versus non-atheroprone regions (thoracic aorta). Collectively, these data demonstrate that aging results in DNA damage and telomere dysfunction that is greater in ECs than VSMCs and elevated in atheroprone aortic regions.
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Affiliation(s)
- Samuel I Bloom
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
| | - Jordan R Tucker
- Department of Internal Medicine, Division of Geriatrics, University of Utah, VA Medical Center-SLC, GRECC Building 2, Rm 2D15A, 500 Foothill Dr., Salt Lake City, UT, USA
| | - Jisok Lim
- Department of Internal Medicine, Division of Geriatrics, University of Utah, VA Medical Center-SLC, GRECC Building 2, Rm 2D15A, 500 Foothill Dr., Salt Lake City, UT, USA
| | - Tyler G Thomas
- Department of Internal Medicine, Division of Geriatrics, University of Utah, VA Medical Center-SLC, GRECC Building 2, Rm 2D15A, 500 Foothill Dr., Salt Lake City, UT, USA
| | - Gregory J Stoddard
- Department of Internal Medicine, Division of Geriatrics, University of Utah, VA Medical Center-SLC, GRECC Building 2, Rm 2D15A, 500 Foothill Dr., Salt Lake City, UT, USA
| | - Lisa A Lesniewski
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
- Department of Internal Medicine, Division of Geriatrics, University of Utah, VA Medical Center-SLC, GRECC Building 2, Rm 2D15A, 500 Foothill Dr., Salt Lake City, UT, USA
- Geriatric Research and Clinical Center, Veteran's Affairs Medical Center-Salt Lake City, Salt Lake City, UT, USA
- Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA
| | - Anthony J Donato
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA.
- Department of Internal Medicine, Division of Geriatrics, University of Utah, VA Medical Center-SLC, GRECC Building 2, Rm 2D15A, 500 Foothill Dr., Salt Lake City, UT, USA.
- Geriatric Research and Clinical Center, Veteran's Affairs Medical Center-Salt Lake City, Salt Lake City, UT, USA.
- Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA.
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA.
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Bloom SI, Tucker JR, Liu Y, Abdeahad H, Machin DR, Thomas TG, Bramwell RC, Islam MT, Lesniewski LA, Donato AJ. Aging results in endothelial cell telomere uncapping that induces senescence and physiological dysfunction. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r4606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Samuel I. Bloom
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | | | - Yu Liu
- Department of GeriatricsTongji HospitalWuhan
| | - Hossein Abdeahad
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Daniel R. Machin
- Department oof Nutrition, Food, and Exercise SciencesFlorida State UniversityTallahasseeFL
| | | | | | - Md Torikul Islam
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Lisa A. Lesniewski
- Geriatric Research, Education and Clinical CenterVeterans Affairs Medical Center Salt Lake CitySalt Lake CityUT
- Nutrition and Integrative PhysiologyVeterans Affairs Medical Center Salt Lake CitySalt Lake CityUT
- Internal MedicineVeterans Affairs Medical Center Salt Lake CitySalt Lake CityUT
| | - Anthony J. Donato
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Internal MedicineUniversity of UtahSalt Lake CityUT
- BiochemistryUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education and Clinical CenterUniversity of UtahSalt Lake CityUT
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Thomas TG. Book Review: John Charnley: The Man and the Hip. J R Soc Med 2018. [DOI: 10.1177/014107689008301133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Kazi HA, Thomas TG. Use of a sharps bin to provide lower limb traction. Ann R Coll Surg Engl 2012. [PMID: 22943237 PMCID: PMC3954382 DOI: 10.1308/003588412x13373405385214b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- H A Kazi
- Wirral University Teaching Hospital NHS Foundation Trust, UK.
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Kazi HA, Thomas TG. Use of a sharps bin to provide lower limb traction. Ann R Coll Surg Engl 2012; 94:360. [DOI: 10.1308/rcsann.2012.94.5.360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- HA Kazi
- Wirral University Teaching Hospital NHS Foundation Trust,UK
| | - TG Thomas
- Wirral University Teaching Hospital NHS Foundation Trust,UK
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Singh S, Thomas TG, Singh SK, Chauhan LS. Declining trend of lymphatic filariasis from rural areas of Koraput district of Odisha State. J Commun Dis 2011; 43:277-279. [PMID: 23785747] [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] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
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Singh SP, Raghavendra K, Thomas TG. Mosquito larvicidal properties of aqueous and acetone extracts of Trianthema portulacastrum Linn. (family: Aizoaceae) against vector species of mosquitoes. J Commun Dis 2011; 43:237-241. [PMID: 23781639] [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: 06/02/2023]
Abstract
Crude aqueous and acetone extracts of leaf of Trianthema portulacastrum was evaluated for its mosquito larvicidal properties against the larvae of four vector species of mosquito under laboratory conditions. These extracts showed good larvicidal properties, 100% mortality in the third instar larvae was observed in the larval bioassay test with Anopheles culicifacies, Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti at a concentration of 1.0, 0.75, 0.75 and 1.0% respectively. The LD50 values estimated for aqueous extract against the larvae of An. culicifacies, An. stephensi, Cx. quinquefasciatus and Ae. aegypti were 0.17, 0.15, 0.18 and 0.17% and LD90 values were 0.57, 0.58, 0.76, and 0.75% respectively. The LD50 values estimated for acetone extract against the larvae of An. culicifacies, An. stephensi, Cx. quinquefasciatus and Ae. aegypti were 0.09, 0.10, 0.09 and 0.12 % and LD90 values were 0.28, 0.25, 0.26 and 0.26% respectively. It is observed that the acetone extract is more effective as compared to aqueous extract. Trianthema portulacastrum can be considered as a probable source of photochemical used for the development of larvicide against disease vectors.
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Affiliation(s)
- S P Singh
- National Institute of Malaria Research (ICMR), Sec-8, Dwarka, New Delhi-110077, India.
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Parkash V, Somani H, Thomas TG, Kumbhat S. Mosquito larvicidal properties of latex of Pedilanthus tithymaloides (L) (family: Euphorbiaceae). J Commun Dis 2009; 41:129-131. [PMID: 22010502] [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] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Affiliation(s)
- Ved Parkash
- Biosensor laboratory, Department of Chemistry, Jai Narayan Vyas University, Jodhpur-342 033
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Sharma SN, Kumar S, Das BP, Thomas TG, Kumar K, Katyal R, Gill KS, Bora D, Lal S, Saxena VK. Entomological indices of Aedes aegypti at some international airports and seaports of southern India--a report. J Commun Dis 2005; 37:173-81. [PMID: 17080700] [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: 05/12/2023]
Abstract
Entomological surveys were undertaken at some of the international airports/seaports (Bangalore, Calicut, Chennai, Cochin, Thiruvanathapuram and Vishakapatnam) to find out the breeding prevalence of dengue vector mosquito in diverse breeding containers from 1998 to 2004. Three vector indices (House index, Container index and Breateu index) were used to assess the breeding potential at each airport/seaport. International Health Regulations urged national governments to keep all the international airports/seaports and peripheral areas up to 400 meters free from Aedes aegypti mosquitoes. However, surveys revealed high vector indices at all the airports and seaports. Health authorities of airports/seaports need to take cognizance of these facts and develop action plan for appropriate control measures with emphasis on vector surveillance.
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Affiliation(s)
- S N Sharma
- National Institute of Communicable Diseases, 22-Shamnath Marg, Delhi-54
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Kumar K, Saxena VK, Thomas TG, Lal S. Outbreak investigation of scrub Typhus in Himachal Pradesh (India). J Commun Dis 2004; 36:277-83. [PMID: 16506551] [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: 05/06/2023]
Abstract
Scrub Typhus outbreak investigation was undertaken during September 2003 in the three worst affected districts Shimla, Solan and Sirmaur in Himachal Pradesh (India). A total of 113 cases and 19 deaths (17.27 percent case fatality rate) were reported from the eight districts, which were reporting cases. Cases were prevalent in all age groups and in both the sexes among the persons frequenting forest for occupational work. 35.7 percent of the patients serum samples showed a titer of > 1: 80 against OX 19 and OXK antigen is suggestive of Scrub Typhus. Entomologically Rattus rattus (39.5 per cent) was the most prevalent species followed by Suncus murinus (22.91 percent), Bandicoota bengalensis (29.16 percent) and Bandicoota indica and Mus musculus (4.16 percent each). Vector species Leptotrombidium deliense and Gahrliepia (schoengastilla) sp. were recorded. The chigger index 23.0 was found to be highest in Vill. Baldian and 5.0 in Vill. Bhatakuffer (Shimla) and 1.0 in Vill. Rebon (Solan), which is above the critical limit of 0.69 per rodents. Other mite species, ixodid ticks, fleas and lice have been recorded.
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Affiliation(s)
- Kaushal Kumar
- National Institute of Communicable Diseases, 22 Sham Nath Marg,Delhi-110 054
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Thomas TG, Raghavendra K, Lal S, Saxena VK. Mosquito larvicidal properties of latex from unripe fruits of Carica papaya linn. (Caricaceae). J Commun Dis 2004; 36:290-2. [PMID: 16506553] [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] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Affiliation(s)
- T G Thomas
- National Institute of Communicable Diseases, Marg, Delhi
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Thomas TG, Sharma SK, Prakash A, Sokhey J, Sharma BR. Insecticide susceptibility status of Culex tritaeniorhynchus giles, vector of Japanese encephalitis in Delhi. Jpn J Infect Dis 2000; 53:11-4. [PMID: 10777851] [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: 02/16/2023]
Abstract
Laboratory studies were carried out to ascertain the current susceptibility status of adult and larval stages of the Culex tritaeniorhynchus mosquito, vector of Japanese encephalitis, to various insecticides used under public health programs in India. The present study revealed that exposure of adult mosquitoes to diagnostic concentrations of DDT - 4.0%, malathion - 5.0%, fenitrothion - 1.0%, and propoxur - 0.1% could induce only 50.0, 10. 0, 15.0, and 5.0% mortality, respectively, indicating that the species was resistant to all of these insecticides. The LT50 and LT95 values calculated using diagnostic concentrations of DDT, malathion, fenitrothion, and propoxur were found to be 56.4 and 136, 138 and 272, 185 and 258, and 187 and 249 min, respectively. However, when adult mosquitoes were exposed to the diagnostic concentration of synthetic pyrethroids, viz., deltamethrin - 0.025%, permethrin - 0.25%, and lambdacyhalothrin - 0.1%, 100.0% mortality was observed, indicating that the species was highly susceptible to these adulticides. Larval susceptibility tests carried out using diagnostic dosages of DDT- 0.008, temephos- 0.02, fenthion- 0.008, fenitrothion- 0.125, and malathion- 0.005 mg/l failed to induce any mortality, indicating that larvae were resistant to these larvicides. The LC50 and LC90 values calculated for commonly used larvicides, viz., temephos and fenthion, were 0.1511 and 1.9098, and 0.6151 and 2.395 mg/l, respectively. Increase in tolerance level were estimated at 95.5- and 299.4-fold when these LC90 values were compared with diagnostic dosages of temephos and fenthion, respectively.
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Affiliation(s)
- T G Thomas
- National Institute of Communicable Diseases, Delhi 110054, India
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Kumar K, Jamil-Ur-Rahman S, Sharma SK, Gill KS, Katyal R, Kaur R, Thomas TG, Barua K. Entomological and rodent surveillance in plague-suspected areas during September 1994 and thereafter. Jpn J Med Sci Biol 1997; 50:97-111. [PMID: 9556751 DOI: 10.7883/yoken1952.50.97] [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: 02/07/2023]
Abstract
Studies carried out in the states of Maharashtra, Gujarat, Uttar Pradesh and Union Territory of Delhi after the bubonic plague outbreak during 1994 revealed the presence of seven species of rodents, viz. Rattus rattus, R. norvegicus, Mus. musculus, Tatera indica, Suncus murinus, Bandicoota bengalensis and B. indica. The flea species encountered were Xenopsylla cheopis and X. astia. The X. cheopis and X. astia index recorded in different areas of Beed district of Maharashtra; Surat, Vadodra and Baruch districts in Gujarat and Varanasi district in Uttar Pradesh and their implications have been discussed. Insecticide suspectibility tests carried out against DDT, dieldrin, malathion and deltamethrin with X. cheopis collected from Maharashtra, Delhi and Varanasi revealed that this vector species is resistant to DDT and dieldrin but susceptible to malathion and deltamethrin. The prevalence and distribution of rodents species, high cheopis index and prevalence of Tatera indica just at the door steps of houses in village Mamla of Beed district provides highly congenital conditions for the intermingling of wild and domestic rodents and transfer of flea population from wild to domestic rodents and vice-versa. These conditions were found to be highly supportive for bubonic plague transmission in the district. The presence of Yersinia pestis antibodies in Rattus rattus collected from Beed, Surat and Varanasi areas are also indicative of bubonic plague in Beed and Varanasi and pneumonic plague in Surat during 1994.
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Affiliation(s)
- K Kumar
- Medical Entomology and Vector Control Division, National Institute of Communicable Diseases Sham Nath Marg, Delhi, India
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Abstract
Short stature resulting from spinal deformity in three generations of a family is reported. Multiple vertebral anomalies were found in the proband and are the probable underlying cause of the severe scoliosis seen in the adult members. The pattern of inheritance suggests that an autosomal dominant gene is responsible for this condition, but it may well be the same gene that causes the dominant form of spondylocostal dysostosis, this family representing one end of the spectrum with mild rib changes. The clinical features of spondylocostal dysostosis are reviewed.
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Affiliation(s)
- I K Temple
- Department of Paediatric Genetics, Institute of Child Health, London
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Chandrasekharan A, Ghosh TK, Jain DC, Thomas TG. Relative role of different types of aquatic plants in the production of Mansonia. J Commun Dis 1988; 20:202-8. [PMID: 2908281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Abstract
This paper represents the beginning of a research programme whose aim is to develop a practical method of monitoring the healing progress of fractures. The objectives of the following are to identify the various resonances, and to show the types of modes which exist in long bones in vitro. A model has been evaluated to predict the tibial resonance frequencies. It is composed of a homogeneous, hollow beam with the constant cross section of an isosceles triangle. Such a beam can explain the two main types of fundamental transverse mode along with their triple resonances. The predicted resonances of the transverse waves are less than 5.8% in error in comparison to the measured values. This error increases to 23.8% for the torsional waves due to their different characteristics.
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Abstract
One-hundred-and-five patients were visited at home one year or more after they had been treated for proximal femoral fractures to assess the extent to which their social independence had been affected by the incident. Since the accident 25% had become more dependent. The principal factors contributing to this outcome included established dependence, great age at the time of injury, and a poor clinical result. The implications for social services and community care of preventing social impairment justify a more comprehensive investigation. The need for close co-operation between orthopaedic surgeons and geriatricians, already widely acknowledged, is further emphasized.
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Thomas TG. Duration of recovery from minor injuries. Proc R Soc Med 1970; 63:1153-4. [PMID: 4249565 PMCID: PMC1811714] [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: 01/09/2023]
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Baker WDC, Thomas TG, Kirkaldy-Willis WH. Changes in the cartilage of the posterior intervertebral joints after anterior fusion. J Bone Joint Surg Br 1969; 51:736-46. [PMID: 5309013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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