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Full-Text Articles in Life Sciences
Validity Of Boston Marathon Qualifying Times, Paul M. Vanderburgh
Validity Of Boston Marathon Qualifying Times, Paul M. Vanderburgh
Paul M. Vanderburgh
Purpose: To assess the validity of Boston Marathon qualifying (BMQ) standards for men and women. Methods: Percent differences between BMQ and current world records (WR) by sex and age group were computed. WR was chosen as the criterion comparison because it is not confounded by intensity, body composition, lifestyle, or environmental factors. A consistent difference across age groups would indicate an appropriate slope of the age-vs-BMQ curve. Inconsistent differences were corrected by adjusting BMQ standards to achieve a uniform percentage difference from WR. Results: BMQ standards for men were consistently ~50% slower than WR (mean 51.5% ± 1.4%, range 49.6–54.4%), …
Neuromuscular Adaptations In Elderly Adults Are Task-Specific During Stepping And Obstacle Clearance Tasks., Matthew Bice, Nicholas J. Hanson, James A. Eldridge, Paul Reneau, Douglas W. Powell
Neuromuscular Adaptations In Elderly Adults Are Task-Specific During Stepping And Obstacle Clearance Tasks., Matthew Bice, Nicholas J. Hanson, James A. Eldridge, Paul Reneau, Douglas W. Powell
James Eldridge
Elderly adults have a diminished movement capacity due to physiological and neurological declines associated with advancing age. Previous research suggests that elderly adults use altered neuromuscular patterns to conduct activities of daily living (ADLs). Limited research has addressed these altered activation strategies in obstacle clearance, stair ascent and stair descent. The purpose of this study was to compare neuromuscular activation patterns in young and elderly adults during these tasks. Eleven young and 10 healthy elderly adults performed five downward stepping, upward stepping and obstacle clearance trials. Surface EMG was measured from the quadriceps, hamstrings, gastrocnemius and tibialis anterior muscles. A …
Tradeoffs Of Warm Adaptation In Aquatic Ectotherms: Live Fast, Die Young?, Eloy Martinez, Anthony P. Porreca, Robert E. Colombo, Michael A. Menze
Tradeoffs Of Warm Adaptation In Aquatic Ectotherms: Live Fast, Die Young?, Eloy Martinez, Anthony P. Porreca, Robert E. Colombo, Michael A. Menze
Eloy Martinez
In the face of a changing climate, questions regarding sub-lethal effects of elevated habitat temperature on the physiology of ectotherms remain unanswered. In particular, long-term responses of ectotherms to the warming trend in tropical regions are unknown, and understudied due to the difficulties in specimen and community traceability. In freshwater lakes employed as cooling reservoirs for power plants, increased physiological stress from high water temperature can potentially alter the community structure of fishes. We employ this highly tractable system to assess how thermal regimes can alter the physiology and ecology of aquatic species. We documented a significantly reduced lifespan, growth …
Developmental Expression Of A Candidate Mullerian Inhibiting Substance Type Ii Receptor, Jose Teixeira, Wei He, Paresh Shah, Nobuyuki Morikawa, Mary Lee, Elizabeth Catlin, Peter Hudson, John Wing, David Maclaughlin, Patricia Donahoe
Developmental Expression Of A Candidate Mullerian Inhibiting Substance Type Ii Receptor, Jose Teixeira, Wei He, Paresh Shah, Nobuyuki Morikawa, Mary Lee, Elizabeth Catlin, Peter Hudson, John Wing, David Maclaughlin, Patricia Donahoe
Mary M. Lee
We have isolated a candidate Mullerian inhibiting substance (MIS) type II receptor complementary DNA from an embryonic rat urogenital ridge library and have studied its binding to MIS, its developmental pattern of expression and tissue distribution. By in situ hybridization with a full-length riboprobe, the receptor is expressed in the mesenchymal cells surrounding the Mullerian duct at embryonic days 14, 15, and 16 and in tubular and follicular structures of the rat fetal gonads. Expression of the messenger RNA was also seen in the granules cells and seminiferous tubules of pubertal gonads. Northern analysis revealed that the MIS type II …
Developmentally Regulated Polyadenylation Of Two Discrete Messenger Ribonucleic Acids For Mullerian Inhibiting Substance, Mary Lee, Richard Cate, Patricia Donahoe, Gerald Waneck
Developmentally Regulated Polyadenylation Of Two Discrete Messenger Ribonucleic Acids For Mullerian Inhibiting Substance, Mary Lee, Richard Cate, Patricia Donahoe, Gerald Waneck
Mary M. Lee
Mullerian inhibiting substance (MIS) is a 140-kilodalton homodimeric glycoprotein that causes regression of the Mullerian ducts in male embryos, and may also have a role in both males and females in the regulation of germ cell maturation. We examined the ontogeny of MIS messenger RNA (mRNA) in rat testes from midgestation through adulthood and found two discrete MIS mRNA species that are developmentally regulated. The larger 2.0-kilobase species is abundant at embryonic day 14, then decreases in late gestation, and is barely detectable after birth. The smaller 1.8-kilobase species is first noted at embryonic day 18 and is the major …
Mullerian Inhibiting Substance Ontogeny And Its Modulation By Follicle-Stimulating Hormone In The Rat Testes, Tatsuo Kuroda, Mary Lee, Christopher Haqq, David Powell, Thomas Manganaro, Patricia Donahoe
Mullerian Inhibiting Substance Ontogeny And Its Modulation By Follicle-Stimulating Hormone In The Rat Testes, Tatsuo Kuroda, Mary Lee, Christopher Haqq, David Powell, Thomas Manganaro, Patricia Donahoe
Mary M. Lee
Mullerian Inhibiting Substance (MIS) production in rat testes from the late fetal to the adult period and its modulation by gonadotropins in neonatal testes were studied using immunohistochemistry, northern analysis, and a graded organ culture bioassay for MIS. The intense immunohistochemical staining for MIS seen in fetal and newborn testes began to decrease gradually after the third postnatal day, then decreased dramatically on the fifth postnatal day. MIS immunohistochemical activity was then present at a low level until about the 20th postnatal day, after which it was barely detectable. The testes from rats treated with FSH at birth showed a …
Developmental Changes In Mullerian Inhibiting Substance In The Cynomolgus Monkey, Macaca Fascicularis, Mary Lee, M. Gustafson, Etsuji Ukiyama, Patricia Donahoe, David Maclaughlin, Michael Wexler, Hugh Keeping
Developmental Changes In Mullerian Inhibiting Substance In The Cynomolgus Monkey, Macaca Fascicularis, Mary Lee, M. Gustafson, Etsuji Ukiyama, Patricia Donahoe, David Maclaughlin, Michael Wexler, Hugh Keeping
Mary M. Lee
Mullerian inhibiting substance (MIS) is a glycoprotein hormone produced in Sertoli cells of the fetal and postnatal testis, and granulosa cells of the pubertal ovary. We examined MIS expression in a nonhuman primate, the cynomolgus macaque monkey (Macaca fascicularis), to define an animal model for studying MIS gene regulation. Changes in testicular MIS mRNA with age were assessed by in situ hybridization of prepubertal to adult testes, Northern analysis of pubertal and adult specimens, and determination of serum MIS concentrations from infancy to adulthood. We found that MIS expression was highest in the youngest animals and decreased progressively with increasing …
Variations In Body Mass Index With Age In Masters Athletes, Joe Walsh, Mike Climstein, Ian Timothy Heazlewood, Stephen Burke, Jyrki Kettunen, Kent Adams, Mark Debeliso
Variations In Body Mass Index With Age In Masters Athletes, Joe Walsh, Mike Climstein, Ian Timothy Heazlewood, Stephen Burke, Jyrki Kettunen, Kent Adams, Mark Debeliso
Mike Climstein
Whilst there is growing evidence that activity across the lifespan is beneficial for improved health, there are also many changes involved with the aging process and subsequently the potential for reduced indices of health. The nexus between health, physical activity and aging is complex and has raised much interest in recent times due to the realization that a multifaceted approached is necessary in order to counteract a growing obesity epidemic. By investigating age based trends within a population adhering to competitive sport at older ages, further insight might be gleaned to assist in understanding one of many factors influencing this …