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Tyshkovskiy A, Ma S, Shindyapina AV, Tikhonov S, Lee SG, Bozaykut P, Castro JP, Seluanov A, Schork NJ, Gorbunova V, Dmitriev SE, Miller RA, Gladyshev VN. Distinct longevity mechanisms across and within species and their association with aging. Cell 2023; 186:2929-2949.e20. [PMID: 37269831 DOI: 10.1016/j.cell.2023.05.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [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: 12/03/2021] [Revised: 12/29/2022] [Accepted: 05/02/2023] [Indexed: 06/05/2023]
Abstract
Lifespan varies within and across species, but the general principles of its control remain unclear. Here, we conducted multi-tissue RNA-seq analyses across 41 mammalian species, identifying longevity signatures and examining their relationship with transcriptomic biomarkers of aging and established lifespan-extending interventions. An integrative analysis uncovered shared longevity mechanisms within and across species, including downregulated Igf1 and upregulated mitochondrial translation genes, and unique features, such as distinct regulation of the innate immune response and cellular respiration. Signatures of long-lived species were positively correlated with age-related changes and enriched for evolutionarily ancient essential genes, involved in proteolysis and PI3K-Akt signaling. Conversely, lifespan-extending interventions counteracted aging patterns and affected younger, mutable genes enriched for energy metabolism. The identified biomarkers revealed longevity interventions, including KU0063794, which extended mouse lifespan and healthspan. Overall, this study uncovers universal and distinct strategies of lifespan regulation within and across species and provides tools for discovering longevity interventions.
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Affiliation(s)
- Alexander Tyshkovskiy
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119234, Russia
| | - Siming Ma
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Anastasia V Shindyapina
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Stanislav Tikhonov
- Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119234, Russia
| | - Sang-Goo Lee
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Perinur Bozaykut
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Department of Molecular Biology and Genetics, Faculty of Engineering and Natural Sciences, Acibadem Mehmet Ali Aydinlar University, Istanbul 34752, Turkey
| | - José P Castro
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; i3S, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; Aging and Aneuploidy Laboratory, IBMC, Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
| | - Andrei Seluanov
- Departments of Biology and Medicine, University of Rochester, Rochester, NY, USA
| | - Nicholas J Schork
- Quantitative Medicine and Systems Biology Division, Translational Genomics Research Institute, Phoenix, AZ, USA
| | - Vera Gorbunova
- Departments of Biology and Medicine, University of Rochester, Rochester, NY, USA
| | - Sergey E Dmitriev
- Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119234, Russia
| | - Richard A Miller
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, MI 48109, USA
| | - Vadim N Gladyshev
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Broad Institute, Cambridge, MA, USA.
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Shindyapina AV, Cho Y, Kaya A, Tyshkovskiy A, Castro JP, Deik A, Gordevicius J, Poganik JR, Clish CB, Horvath S, Peshkin L, Gladyshev VN. Rapamycin treatment during development extends life span and health span of male mice and Daphnia magna. Sci Adv 2022; 8:eabo5482. [PMID: 36112674 PMCID: PMC9481125 DOI: 10.1126/sciadv.abo5482] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 07/26/2022] [Indexed: 05/22/2023]
Abstract
Development is tightly connected to aging, but whether pharmacologically targeting development can extend life remains unknown. Here, we subjected genetically diverse UMHET3 mice to rapamycin for the first 45 days of life. The mice grew slower and remained smaller than controls for their entire lives. Their reproductive age was delayed without affecting offspring numbers. The treatment was sufficient to extend the median life span by 10%, with the strongest effect in males, and helped to preserve health as measured by frailty index scores, gait speed, and glucose and insulin tolerance tests. Mechanistically, the liver transcriptome and epigenome of treated mice were younger at the completion of treatment. Analogous to mice, rapamycin exposure during development robustly extended the life span of Daphnia magna and reduced its body size. Overall, the results demonstrate that short-term rapamycin treatment during development is a novel longevity intervention that acts by slowing down development and aging, suggesting that aging may be targeted already early in life.
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Affiliation(s)
| | - Yongmin Cho
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Alaattin Kaya
- Department of Biology, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Alexander Tyshkovskiy
- Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119234, Russia
| | - José P. Castro
- Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Amy Deik
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | | | - Jesse R. Poganik
- Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Clary B. Clish
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Steve Horvath
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Leonid Peshkin
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
- Eugene Bell Center for Regenerative Biology and Tissue Engineering and National Xenopus Resource, Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Vadim N. Gladyshev
- Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- Corresponding author.
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Reeg S, Castro JP, Hugo M, Grune T. Accumulation of polyubiquitinated proteins: A consequence of early inactivation of the 26S proteasome. Free Radic Biol Med 2020; 160:293-302. [PMID: 32822745 DOI: 10.1016/j.freeradbiomed.2020.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 08/10/2020] [Accepted: 08/11/2020] [Indexed: 11/18/2022]
Abstract
The proteasomal degradation system is one of the most important protein degradation systems in the cytosol and nucleus. This system is present in two major forms: the ATP-stimulated 26S/30 S proteasome or the ATP-independent 20S core proteasome. While the first recognize ubiquitin-tagged target proteins and degrade them, the 20S proteasome works also independent from ATP, but requires partially unfolded substrates. While the role of the proteasome in the selective removal of oxidized proteins is undoubted, the debate about a selective ubiquitination of oxidized proteins is still ongoing. Here we demonstrate, that under some conditions of oxidative stress an accumulation of oxidized and of K48-ubiquitinated proteins occurs. However, the removal of oxidized proteins seems not to be linked to ubiquitination. In further experiments, we could show that the accumulation of ubiquitinated proteins under certain oxidative stress conditions is rather a result of a different sensitivity of the 26S proteasome and the ubiquitination machinery towards oxidants.
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Affiliation(s)
- Sandra Reeg
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbrücke, 14558, Nuthetal, Germany
| | - José P Castro
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbrücke, 14558, Nuthetal, Germany; German Center for Diabetes Research (DZD), 85764, München-Neuherberg, Germany
| | - Martin Hugo
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbrücke, 14558, Nuthetal, Germany
| | - Tilman Grune
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbrücke, 14558, Nuthetal, Germany; German Center for Diabetes Research (DZD), 85764, München-Neuherberg, Germany; German Center for Cardiovascular Research (DZHK), 10117, Berlin, Germany; University of Potsdam, Institute of Nutritional Science, 14558, Nuthetal, Germany.
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Henkel J, Alfine E, Saín J, Jöhrens K, Weber D, Castro JP, König J, Stuhlmann C, Vahrenbrink M, Jonas W, Kleinridders A, Püschel GP. Soybean Oil-Derived Poly-Unsaturated Fatty Acids Enhance Liver Damage in NAFLD Induced by Dietary Cholesterol. Nutrients 2018; 10:nu10091326. [PMID: 30231595 PMCID: PMC6164134 DOI: 10.3390/nu10091326] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 09/14/2018] [Accepted: 09/14/2018] [Indexed: 12/12/2022] Open
Abstract
While the impact of dietary cholesterol on the progression of atherosclerosis has probably been overestimated, increasing evidence suggests that dietary cholesterol might favor the transition from blunt steatosis to non-alcoholic steatohepatitis (NASH), especially in combination with high fat diets. It is poorly understood how cholesterol alone or in combination with other dietary lipid components contributes to the development of lipotoxicity. The current study demonstrated that liver damage caused by dietary cholesterol in mice was strongly enhanced by a high fat diet containing soybean oil-derived ω6-poly-unsaturated fatty acids (ω6-PUFA), but not by a lard-based high fat diet containing mainly saturated fatty acids. In contrast to the lard-based diet the soybean oil-based diet augmented cholesterol accumulation in hepatocytes, presumably by impairing cholesterol-eliminating pathways. The soybean oil-based diet enhanced cholesterol-induced mitochondrial damage and amplified the ensuing oxidative stress, probably by peroxidation of poly-unsaturated fatty acids. This resulted in hepatocyte death, recruitment of inflammatory cells, and fibrosis, and caused a transition from steatosis to NASH, doubling the NASH activity score. Thus, the recommendation to reduce cholesterol intake, in particular in diets rich in ω6-PUFA, although not necessary to reduce the risk of atherosclerosis, might be sensible for patients suffering from non-alcoholic fatty liver disease.
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Affiliation(s)
- Janin Henkel
- Department of Nutritional Biochemistry, Institute of Nutritional Science, University of Potsdam, D-14558 Nuthetal, Germany.
| | - Eugenia Alfine
- German Institute of Human Nutrition, Junior Research Group Central Regulation of Metabolism; D-14558 Nuthetal, Germany.
- German Center for Diabetes Research (DZD), D-85764 München-Neuherberg, Germany.
| | - Juliana Saín
- Department of Nutritional Biochemistry, Institute of Nutritional Science, University of Potsdam, D-14558 Nuthetal, Germany.
- Department of Biological Sciences, Food Science and Nutrition, Faculty of Biochemistry and Biological Sciences, National University of the Litoral (UNL), Santa Fe S3000, Argentina.
| | - Korinna Jöhrens
- Institute of Pathology, Carl Gustav Carus University Hospital Dresden; D-01307 Dresden, Germany.
| | - Daniela Weber
- Department of Molecular Toxicology, German Institute of Human Nutrition; D-14558 Nuthetal, Germany.
| | - José P Castro
- Department of Molecular Toxicology, German Institute of Human Nutrition; D-14558 Nuthetal, Germany.
- Department of Medicine, Division of Genetics, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
| | - Jeannette König
- Department of Molecular Toxicology, German Institute of Human Nutrition; D-14558 Nuthetal, Germany.
| | - Christin Stuhlmann
- Department of Nutritional Biochemistry, Institute of Nutritional Science, University of Potsdam, D-14558 Nuthetal, Germany.
| | - Madita Vahrenbrink
- Department of Nutritional Biochemistry, Institute of Nutritional Science, University of Potsdam, D-14558 Nuthetal, Germany.
| | - Wenke Jonas
- German Center for Diabetes Research (DZD), D-85764 München-Neuherberg, Germany.
- Department of Experimental Diabetology, German Institute of Human Nutrition; D-14558 Nuthetal, Germany.
| | - André Kleinridders
- German Institute of Human Nutrition, Junior Research Group Central Regulation of Metabolism; D-14558 Nuthetal, Germany.
- German Center for Diabetes Research (DZD), D-85764 München-Neuherberg, Germany.
| | - Gerhard P Püschel
- Department of Nutritional Biochemistry, Institute of Nutritional Science, University of Potsdam, D-14558 Nuthetal, Germany.
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Sant'Anna JFM, Moraes-Neto A, Castro JP, Sczepanski TS, Pohv JA, Lopera-Barrero N, Artoni RF. Quantitative and qualitative variables of semen from surubim do Iguaçu, Steindachneridion melanodermatum Garavello, 2005 (Siluriformes: Pimelodidae). BRAZ J BIOL 2018; 79:1-5. [PMID: 29590249 DOI: 10.1590/1519-6984.09016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 08/30/2017] [Indexed: 11/22/2022] Open
Abstract
The objective of the present work was to assess the qualitative and quantitative characteristics of semen from the surubim do Iguaçu (Steindachneridion melanodermatum). Induced spermiation was achieved in eleven males with mean weight of 1.76 ± 0.48 kg and average age of two years and semen was collected by stripping. The average volume was 1.34 ± 0.73 mL. The duration of sperm motility was 154.4 ± 72.6 and 149.0 ± 77.5 seconds after activation with hatchery water and distilled water, respectively. The sperm concentration estimated by hemocytometer was 5.423 ± 2.155 x 1010 spermatozoa/mL. The results indicate that S. melanodermatum semen is easily obtained during the spawning season and the seminal characteristics are adequate insemination and subsequent in vitro fertilization.
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Affiliation(s)
- J F M Sant'Anna
- Programa de Pós-graduação em Biologia Evolutiva, Universidade Estadual de Ponta Grossa - UEPG, Av. Carlos Cavalcanti, 4748, CEP 84030-900, Ponta Grossa, PR, Brasil
| | - A Moraes-Neto
- Programa de Pós-graduação em Ciência Animal, Universidade Federal de Mato Grosso do Sul - UFMS, Av. Senador Felinto Müller, 2443, CEP 79070-900, Campo Grande, MS, Brasil
| | - J P Castro
- Programa de Pós-graduação em Genética Evolutiva e Biologia Molecular, Universidade Federal de São Carlos - UFSCar, Rodovia Washington Luiz, Km 235, CEP 13560-970, São Carlos, SP, Brasil
| | - T S Sczepanski
- Programa de Pós-graduação em Biologia Evolutiva, Universidade Estadual de Ponta Grossa - UEPG, Av. Carlos Cavalcanti, 4748, CEP 84030-900, Ponta Grossa, PR, Brasil
| | - J A Pohv
- Programa de Pós-graduação em Ciência Animal, Universidade Federal de Mato Grosso do Sul - UFMS, Av. Senador Felinto Müller, 2443, CEP 79070-900, Campo Grande, MS, Brasil
| | - N Lopera-Barrero
- Programa de Pós-graduação em Ciência Animal, Universidade Estadual de Londrina - UEL, Rod. Cendo Garcia Cid, Pr 445, Km 380, CEP 86057-970, Londrina, PR, Brasil
| | - R F Artoni
- Programa de Pós-graduação em Biologia Evolutiva, Universidade Estadual de Ponta Grossa - UEPG, Av. Carlos Cavalcanti, 4748, CEP 84030-900, Ponta Grossa, PR, Brasil.,Programa de Pós-graduação em Genética Evolutiva e Biologia Molecular, Universidade Federal de São Carlos - UFSCar, Rodovia Washington Luiz, Km 235, CEP 13560-970, São Carlos, SP, Brasil
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Wardelmann K, Castro JP, Rath M, Kleinridders A. Chaperone Hsp10: A key player for mitochondrial function and central insulin sensitivity. DIABETOL STOFFWECHS 2017. [DOI: 10.1055/s-0037-1601725] [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: 10/19/2022]
Affiliation(s)
- K Wardelmann
- German Institute of Human Nutrition (DIfE), Junior Research Group Central Regulation of Metabolism, Nuthetal, Germany
| | - JP Castro
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - M Rath
- German Institute of Human Nutrition (DIfE), Junior Research Group Central Regulation of Metabolism, Nuthetal, Germany
| | - A Kleinridders
- German Institute of Human Nutrition (DIfE), Junior Research Group Central Regulation of Metabolism, Nuthetal, Germany
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Reeg S, Jung T, Castro JP, Davies KJA, Henze A, Grune T. The molecular chaperone Hsp70 promotes the proteolytic removal of oxidatively damaged proteins by the proteasome. Free Radic Biol Med 2016; 99:153-166. [PMID: 27498116 PMCID: PMC5201141 DOI: 10.1016/j.freeradbiomed.2016.08.002] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 07/19/2016] [Accepted: 08/01/2016] [Indexed: 01/23/2023]
Abstract
One hallmark of aging is the accumulation of protein aggregates, promoted by the unfolding of oxidized proteins. Unraveling the mechanism by which oxidized proteins are degraded may provide a basis to delay the early onset of features, such as protein aggregate formation, that contribute to the aging phenotype. In order to prevent aggregation of oxidized proteins, cells recur to the 20S proteasome, an efficient turnover proteolysis complex. It has previously been shown that upon oxidative stress the 26S proteasome, another form, dissociates into the 20S form. A critical player implicated in its dissociation is the Heat Shock Protein 70 (Hsp70), which promotes an increase in free 20S proteasome and, therefore, an increased capability to degrade oxidized proteins. The aim of this study was to test whether or not Hsp70 is involved in cooperating with the 20S proteasome for a selective degradation of oxidatively damaged proteins. Our results demonstrate that Hsp70 expression is induced in HT22 cells as a result of mild oxidative stress conditions. Furthermore, Hsp70 prevents the accumulation of oxidized proteins and directly promotes their degradation by the 20S proteasome. In contrast the expression of the Heat shock cognate protein 70 (Hsc70) was not changed in recovery after oxidative stress and Hsc70 has no influence on the removal of oxidatively damaged proteins. We were able to demonstrate in HT22 cells, in brain homogenates from 129/SV mice and in vitro, that there is an increased interaction of Hsp70 with oxidized proteins, but also with the 20S proteasome, indicating a role of Hsp70 in mediating the interaction of oxidized proteins with the 20S proteasome. Thus, our data clearly implicate an involvement of Hsp70 oxidatively damaged protein degradation by the 20S proteasome.
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Affiliation(s)
- Sandra Reeg
- German Institute of Human Nutrition Potsdam Rehbruecke (DIfE), Department of Molecular Toxicology, 14588 Nuthetal, Germany
| | - Tobias Jung
- German Institute of Human Nutrition Potsdam Rehbruecke (DIfE), Department of Molecular Toxicology, 14588 Nuthetal, Germany; German Center for Diabetes Research (DZD), Germany
| | - José P Castro
- German Institute of Human Nutrition Potsdam Rehbruecke (DIfE), Department of Molecular Toxicology, 14588 Nuthetal, Germany; German Center for Diabetes Research (DZD), Germany
| | - Kelvin J A Davies
- University of Southern California, Leonard Davis School of Gerontology, and Division of Molecular & Computational Biology, Dornsife College of Letters, Arts, and Sciences, Los Angeles, CA 90089-0191, USA
| | - Andrea Henze
- University Potsdam, Institute of Nutritional Science, Department of Physiology and Pathophysiology, 14588 Nuthetal, Germany
| | - Tilman Grune
- German Institute of Human Nutrition Potsdam Rehbruecke (DIfE), Department of Molecular Toxicology, 14588 Nuthetal, Germany; German Center for Diabetes Research (DZD), Germany.
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Abstract
This paper describes a navigation architecture for mobile robots, structured as a set of nested control loops whose depth is related to their knowledge of the environment and the ability to drive the actuator, and involving as well competing behaviors that will ultimately generate the robot motion. The architecture has been successfully used on a mobile platform to support three-dimensional environment reconstruction tasks. The architecture may be classified as belonging to the hybrid type but made up of hybrid elements as well, allowing virtually any level of input awareness and ranging from high-level task planning to direct motion commands issued by external user or applications. A monitorized data path ensures the construction of the most adequate and safe motion, as well as an unlimited set of behaviors depending on the already known and perceived environment. Added concepts of path recovering and assisted navigation fulfill the demands for the three-dimensional acquisition scheme involved. Some comparison with existing architectures is carried out throughout the text. The versatility and robustness of the architecture are supported by extensive results.
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Affiliation(s)
- Vitor M. Santos
- Universidade de Aveiro, Centro de Tecnologia Mecânica e Automação, Campus Universitário, 3810-193 Aveiro, Portugal
| | - José P. Castro
- Instituto Superior Técnico, Instituto de Sistemas e Robótica, Av.Rovisco Pais 1, 1049-001 Lisboa, Portugal
| | - M. Isabel Ribeiro
- Instituto Superior Técnico, Instituto de Sistemas e Robótica, Av.Rovisco Pais 1, 1049-001 Lisboa, Portugal
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Machado LP, Castro JP, Madi-Ravazzi L. Evaluation of the courtship and of the hybrid male sterility among Drosophila buzzatii cluster species (Diptera, Drosophilidae). BRAZ J BIOL 2002; 62:601-8. [PMID: 12659009 DOI: 10.1590/s1519-69842002000400007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [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: 11/22/2022] Open
Abstract
In the Drosophila repleta group the establishment of subgroups and complexes made on the basis of morphological and cytological evidences is supported by tests of reproductive isolation. Among species in the repleta group, the buzzatii cluster, due to its polymorphism and polytipism, is an excellent material for ecological and speciation studies. Some interspecific crosses involving Drosophila seriema, Drosophila sp. B, D. koepferae and D. buzzatii strains were completely sterile while others involving strains from these species produced F1 hybrids that did not yield F2. In the present work, data on courtship duration and copula occurrence obtained in the analysis of flies from parental sterile crosses and on spermatozoon mobility observed in F1 hybrids that did not yield F2 are presented. Copula did not occur during one hour of observation and the spermatozoon also did not show mobility at any of the analyzed stages (3, 7, 9 and 10 days old). There was a high variation in courtship average duration and in the percentage of males that courted the females. The reproductive isolation mechanisms indicated by these observations were pre and post-zygotic, as supported by the absence of copula and male sterility. Data obtained also showed the occurrence of different degrees of reproductive compatibility among the strains classified as the same species but from distinct geographic localities.
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Affiliation(s)
- L P Machado
- Faculdade de Medicina, Departamento de Genética, Universidade de São Paulo, Ribeirão Preto, Brazil
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Abstract
From 1996 until 2000 we treated 52 humeral shaft fractures with AO unreamed nailing. Mean patient age was 35.8 years and the average follow-up 29.6 months. There were 31 type A fractures, 15 type B, and 6 type C. Closed retrograde nailing was performed in 46 cases and open nailing in six. Functional results were excellent in 48 cases, moderate in three, and poor in one.
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Affiliation(s)
- E S Sanzana
- Department of Orthopedic Surgery, Hospital del Trabajador, Concepción, Chile.
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