Michael P Muehlenbein
Dados Biográficos
| ID | 76635 |
|---|---|
| NOME | Michael P Muehlenbein |
| PRENOMES | Michael P |
| SOBRENOME | Muehlenbein |
| ASSINATURA | MUEHLENBEIN M P |
| AFILIAÇÕES | Indiana University Bloomington |
| ORCID | 0000-0003-1332-6264 |
| VERIFICADO | Sim |
| TOTAL DE OBRAS | 31 |
| TOTAL DE CITAÇÕES | 48 |
| TOTAL COMO AUTOR | 31 |
| TOTAL COMO EDITOR | 0 |
| PRIMEIRO ANO DE PUBLICAÇÃO | 2002 |
| ANO MAIS RECENTE DE PUBLICAÇÃO | 2026 |
| ÍNDICE H | 5 |
Experimental evidence of life history trade-offs during ultra-endurance physical activity
Life history theory seeks to understand how organisms distribute energy between physiological functions across the life course. A central assumption is that energy allocation involves “trade-offs” between competing functions relating to defence, maintenance, reproduction and growth. Constraints on human energy expenditure may produce trade-offs during energetic stress, affecting functions critical for homeostasis, survival and reproduction. While…
Validation of an Enzyme‐Linked Immunosorbent Assay for Measuring Leptin, a Key Metabolic Hormone, in Dried Blood Spot Samples
Objectives Leptin is an established biomarker of appetite regulation and energy status. Problematically, heavy reliance on invasive venipuncture sampling has limited leptin research with diverse human populations and groups such as children. Key questions remain about leptin's evolution and biological roles across the full range of humans. Here, we present and validate a new minimally invasive approach for measuring leptin in finger‐prick dried b…
Age-Dependent Relationships Between Disease Risk and Testosterone Levels
Testosterone levels in men appear to be prognostic of a number of disease outcomes, including severe COVID-19 disease. Testosterone levels naturally decline with age and are lower in individuals with a number of comorbidities and chronic conditions. Low testosterone may therefore be both a cause and a consequence of illness, including COVID-19 disease. The present project examines whether preexisting conditions for severe COVID-19 disease were th…
Waco Covid Survey
Exploring links between pathogen avoidance motivation, Covid ‐19 case counts, and immune function
OBJECTIVES: The selection pressures exerted by pathogens have played important roles in shaping the biology and behavior of animals, including humans. Immune systems recognize and respond to cues of infection or damage by coordinating cellular, humoral, and metabolic shifts that promote recovery. Moreover, animals also possess a repertoire of behavioral tools to help combat the threat of pathogens, often referred to as the behavioral immune syste…
Travel medicine meets conservation medicine in St. Kitts
Despite concern about environmental protection, travelers often underestimate the contribution they may have to disease transmission to other species, as well as the risk of becoming infected themselves. Tourists in general tend to accept more physical risks when traveling than when at home, and much of this can be blamed on the temporary loss of situational awareness and loss of inhibition with a corresponding relaxed attitude toward safety. To …
Religiosity/Spirituality and Physiological Markers of Health
Short‐term resource allocation during extensive athletic competition
OBJECTIVES: Following predictions from life history theory, we sought to identify acute trade-offs between reproductive effort (as measured by psychological arousal) and somatic maintenance (via functional measures of innate immunity) during conditions of severe energetic imbalance. METHODS: Sixty-six male ultramarathon runners (ages 20 to 37 years) were sampled before and after a lengthy race. Saliva and sera were collected for testosterone and …
Primates on display
Human interactions with nonhuman primates vary tremendously, from daily cultural engagements and food commodities, to pet ownership and tourist encounters. These interactions provide opportunities for the exchange of pathogenic organisms (both zoonoses and anthroponoses). As exposures are not limited to areas where bushmeat usage continues to be a major problem, we must work to understand better our motivations for engaging in activities like own…
Disease and Human/Animal Interactions
Understanding pathogen exchange among human, wildlife, and livestock populations, and the varying ecological and cultural contexts in which this exchange takes place, is a major challenge. The present review contextualizes the risk factors that result from human interactions with livestock, companion animals, animal exhibits, wildlife through nature-based tourism, and wildlife through consumption. Given their phylogenetic relatedness to humans, p…
Basics in Human Evolution
Mood, behavior, testosterone, cortisol, and interleukin‐6 in adults during immune activation
OBJECTIVES: Sickness behavior, a suite of behavioral changes subsequent to infection that includes depression, decreased social behaviors, and sleep disturbances, has been well described in model organisms. The phenomenon is relatively unexplored in humans due to methodological difficulties, and hormonal correlates of sickness behavior have not been studied. We therefore attempted to use a vaccine to elicit sickness behaviors outside of a clinica…
Dehydroepiandrosterone and multiple measures of functional immunity in young adults
OBJECTIVES: Human immune function is strongly influenced by variation in hormone concentrations. The adrenal androgens dehydroepiandrosterone (DHEA) and dehydroepiandrosterone-sulfate (DHEA-S) are thought to be beneficial to immune function and disease resistance, but physiologically interact with testosterone and cortisol. We predict that DHEA and DHEA-S will interact with these other hormones in determining immunological outcomes. Understanding…
Androgens and innate immunity in rehabilitated semi‐captive orangutans ( Pongo pygmaeus morio ) from Malaysian Borneo
Despite the implications for the development of life-history traits, endocrine-immune trade-offs in apes are not well studied. This is due, in part, to difficulty in sampling wild primates, and lack of methods available for immune measures using samples collected noninvasively. Evidence for androgen-mediated immune trade-offs in orangutans is virtually absent, and very little is known regarding their pattern of adrenal development and production …
Human sickness behavior
Sickness behavior, a coordinated set of behavioral changes in response to infection, lies at the intersection of immunology, endocrinology, and evolutionary biology. Sickness behavior is elicited by pro‐inflammatory cytokines, is thought to be an adaptive means of redirecting energy away from disadvantageous behaviors and toward mounting an effective immune response, and may be modulated by hormones, including testosterone and oxytocin. Research …
Primate Tourism
Primate tourism is a growing phenomenon, with increasing pressure coming from several directions: the private sector, governments, and conservation agencies. At the same time, some primate sites are working to exclude or severely restrict tourism because of problems that have developed as a result. Indeed, tourism has proven costly to primates due to factors such as disease, stress, social disruption, vulnerability to poachers, and interference w…
Testosterone and Immune Function in Primates
Do chimpanzees (Pan troglodytes schweinfurthii) exhibit sleep related behaviors that minimize exposure to parasitic arthropods? A preliminary report on the possible anti-vector function of chimpanzee …
Hormonal Mechanisms for Regulation of Aggression in Human Coalitions
The costs of dominance
BACKGROUND: Male members of primate species that form multi-male groups typically invest considerable effort into attaining and maintaining high dominance rank. Aggressive behaviors are frequently employed to acquire and maintain dominance status, and testosterone has been considered the quintessential physiological moderator of such behaviors. Testosterone can alter both neurological and musculoskeletal functions that may potentiate pre-existing…
Toward quantifying the usage costs of human immunity
There is a paucity of data on the energetic demands of human immune functions, despite the fact that both clinical medicine and evolutionary biology would benefit from further clarification of these costs. To better understand the energetic requirements of mounting a mild immune response, as well as some of the major hormonal changes underlying these metabolic changes, we examined changes in resting metabolic rate (RMR) and hormones during and af…
Perceived Vaccination Status in Ecotourists and Risks of Anthropozoonoses
Intestinal parasite infections and fecal steroid levels in wild chimpanzees
Immune-endocrine interactions have been evaluated much less frequently in nonhuman primates, and this may be due, in part, to logistical and ethical concerns regarding trapping and sampling of endangered species, especially apes. Using noninvasive fecal collection methods, the present study evaluates possible relationships between fecal steroid levels and gastrointestinal parasite infections in the Ngogo chimpanzee community in Kibale National Pa…
Adaptive variation in testosterone levels in response to immune activation
High testosterone levels reflect investment in male reproductive effort through the ability to produce and maintain muscle tissue and thus augment mate attraction and competitive ability. However, high testosterone levels can also compromise survivorship by increasing risk of prostate cancer, production of oxygen radicals, risk of injury due to hormonally-augmented behaviors such as aggression, violence and risk taking, reduced tissue and organ m…
Testosterone-mediated immune functions and male life histories
Recent advances in human life history theory have provided new insights into the potential selection pressures that were instrumental in the evolution of human and non-human primate males. However, gaps remain in our understanding of how primate males regulate and allocate energetic resources between survivorship and reproductive effort. Defense against parasitic infection is an important force shaping life history evolution. Proper performance o…
Hormonal Mechanisms for Regulation of Aggression in Human Coalitions
Intestinal parasite infections and fecal steroid levels in wild chimpanzees
Immune-endocrine interactions have been evaluated much less frequently in nonhuman primates, and this may be due, in part, to logistical and ethical concerns regarding trapping and sampling of endangered species, especially apes. Using noninvasive fecal collection methods, the present study evaluates possible relationships between fecal steroid levels and gastrointestinal parasite infections in the Ngogo chimpanzee community in Kibale National Pa…
Human sickness behavior
Sickness behavior, a coordinated set of behavioral changes in response to infection, lies at the intersection of immunology, endocrinology, and evolutionary biology. Sickness behavior is elicited by pro‐inflammatory cytokines, is thought to be an adaptive means of redirecting energy away from disadvantageous behaviors and toward mounting an effective immune response, and may be modulated by hormones, including testosterone and oxytocin. Research …
Testosterone and Immune Function in Primates
Disease and Human/Animal Interactions
Understanding pathogen exchange among human, wildlife, and livestock populations, and the varying ecological and cultural contexts in which this exchange takes place, is a major challenge. The present review contextualizes the risk factors that result from human interactions with livestock, companion animals, animal exhibits, wildlife through nature-based tourism, and wildlife through consumption. Given their phylogenetic relatedness to humans, p…
Leptin, adiposity, and testosterone in captive male macaques
Leptin is considered to act as a signal relating somatic energetic status to the reproductive system. However, the nature of that signal and its relationship with male reproductive function across nonhuman primate species are unclear. We suggest that species-specific differences in leptin physiology may be related to the degree of environmental variation and variation in the importance of energy stores for male reproduction. In order to test the …
Primates on display
Human interactions with nonhuman primates vary tremendously, from daily cultural engagements and food commodities, to pet ownership and tourist encounters. These interactions provide opportunities for the exchange of pathogenic organisms (both zoonoses and anthroponoses). As exposures are not limited to areas where bushmeat usage continues to be a major problem, we must work to understand better our motivations for engaging in activities like own…
Adaptive variation in testosterone levels in response to immune activation
High testosterone levels reflect investment in male reproductive effort through the ability to produce and maintain muscle tissue and thus augment mate attraction and competitive ability. However, high testosterone levels can also compromise survivorship by increasing risk of prostate cancer, production of oxygen radicals, risk of injury due to hormonally-augmented behaviors such as aggression, violence and risk taking, reduced tissue and organ m…
Morphological and hormonal parameters in two species of macaques
To compare physiological and developmental differences between two cogeneric species that differ by seasonal vs. aseasonal breeding, values for morphological measurements, testicular volume, serum testosterone, estradiol, and dehydroepiandrosterone-sulfate levels were obtained from 53 rhesus during the early breeding season, as well as 41 pig-tailed macaque males maintained at the Tulane Primate Center. The two species exhibited similar body size…
Morphological and hormonal parameters in two species of macaques
To compare physiological and developmental differences between two cogeneric species that differ by seasonal vs. aseasonal breeding, values for morphological measurements, testicular volume, serum testosterone, estradiol, and dehydroepiandrosterone‐sulfate levels were obtained from 53 rhesus during the early breeding season, as well as 41 pig‐tailed macaque males maintained at the Tulane Primate Center. The two species exhibited similar body size…
Dominance rank and fecal testosterone levels in adult male Chimpanzees ( Pan troglodytes schweinfurthii ) at Ngogo, Kibale National Park, Uganda
In an attempt to describe hormone–behavior interactions in a sample of wild male chimpanzees, we quantified testosterone in 67 fecal samples obtained from 22 adult male chimpanzees at Ngogo, Kibale National Park, Uganda. A mixed‐model methodology that controlled for age‐class identified a significant positive association between testosterone levels and dominance rank. The results are consistent with those reported from a separate, smaller chimpan…
The roles of cats and dogs in the transmission of Toxoplasma infection in Kuna and Embera children in eastern Panama
Dogs may act as mechanical vectors, by rolling in foul-smelling substances and by ingesting fecal material. In areas of high Toxoplasma prevalence in children and where dogs and cats are plentiful, immunocompromised individuals and pregnant women should be warned of the possibility of acquiring Toxoplasma gondii from dogs as well as from soil contaminated by cats. People should be encouraged to wash their hands after contact with soil, dogs, or c…
Testosterone-mediated immune functions and male life histories
Recent advances in human life history theory have provided new insights into the potential selection pressures that were instrumental in the evolution of human and non-human primate males. However, gaps remain in our understanding of how primate males regulate and allocate energetic resources between survivorship and reproductive effort. Defense against parasitic infection is an important force shaping life history evolution. Proper performance o…
Parasitological analyses of the male chimpanzees (Pan troglodytes schweinfurthii) at Ngogo, Kibale National Park, Uganda
Numerous intestinal parasites identified in populations of wild nonhuman primates can be pathogenic to humans. Furthermore, nonhuman primates are susceptible to a variety of human pathogens. Because of increasing human encroachment into previously nonimpacted forests, and the potential for disease transmission between human and nonhuman primate populations, further detailed investigations of primate ecological parasitology are warranted. For mean…
Leptin, adiposity, and testosterone in captive male macaques
Leptin is considered to act as a signal relating somatic energetic status to the reproductive system. However, the nature of that signal and its relationship with male reproductive function across nonhuman primate species are unclear. We suggest that species-specific differences in leptin physiology may be related to the degree of environmental variation and variation in the importance of energy stores for male reproduction. In order to test the …
Intestinal parasite infections and fecal steroid levels in wild chimpanzees
Immune-endocrine interactions have been evaluated much less frequently in nonhuman primates, and this may be due, in part, to logistical and ethical concerns regarding trapping and sampling of endangered species, especially apes. Using noninvasive fecal collection methods, the present study evaluates possible relationships between fecal steroid levels and gastrointestinal parasite infections in the Ngogo chimpanzee community in Kibale National Pa…
Adaptive variation in testosterone levels in response to immune activation
High testosterone levels reflect investment in male reproductive effort through the ability to produce and maintain muscle tissue and thus augment mate attraction and competitive ability. However, high testosterone levels can also compromise survivorship by increasing risk of prostate cancer, production of oxygen radicals, risk of injury due to hormonally-augmented behaviors such as aggression, violence and risk taking, reduced tissue and organ m…
Perceived Vaccination Status in Ecotourists and Risks of Anthropozoonoses
The costs of dominance
BACKGROUND: Male members of primate species that form multi-male groups typically invest considerable effort into attaining and maintaining high dominance rank. Aggressive behaviors are frequently employed to acquire and maintain dominance status, and testosterone has been considered the quintessential physiological moderator of such behaviors. Testosterone can alter both neurological and musculoskeletal functions that may potentiate pre-existing…
Toward quantifying the usage costs of human immunity
There is a paucity of data on the energetic demands of human immune functions, despite the fact that both clinical medicine and evolutionary biology would benefit from further clarification of these costs. To better understand the energetic requirements of mounting a mild immune response, as well as some of the major hormonal changes underlying these metabolic changes, we examined changes in resting metabolic rate (RMR) and hormones during and af…
Hormonal Mechanisms for Regulation of Aggression in Human Coalitions
Do chimpanzees (Pan troglodytes schweinfurthii) exhibit sleep related behaviors that minimize exposure to parasitic arthropods? A preliminary report on the possible anti-vector function of chimpanzee …
Primate Tourism
Primate tourism is a growing phenomenon, with increasing pressure coming from several directions: the private sector, governments, and conservation agencies. At the same time, some primate sites are working to exclude or severely restrict tourism because of problems that have developed as a result. Indeed, tourism has proven costly to primates due to factors such as disease, stress, social disruption, vulnerability to poachers, and interference w…
Testosterone and Immune Function in Primates
Basics in Human Evolution
Mood, behavior, testosterone, cortisol, and interleukin‐6 in adults during immune activation
OBJECTIVES: Sickness behavior, a suite of behavioral changes subsequent to infection that includes depression, decreased social behaviors, and sleep disturbances, has been well described in model organisms. The phenomenon is relatively unexplored in humans due to methodological difficulties, and hormonal correlates of sickness behavior have not been studied. We therefore attempted to use a vaccine to elicit sickness behaviors outside of a clinica…
Dehydroepiandrosterone and multiple measures of functional immunity in young adults
OBJECTIVES: Human immune function is strongly influenced by variation in hormone concentrations. The adrenal androgens dehydroepiandrosterone (DHEA) and dehydroepiandrosterone-sulfate (DHEA-S) are thought to be beneficial to immune function and disease resistance, but physiologically interact with testosterone and cortisol. We predict that DHEA and DHEA-S will interact with these other hormones in determining immunological outcomes. Understanding…
Androgens and innate immunity in rehabilitated semi‐captive orangutans ( Pongo pygmaeus morio ) from Malaysian Borneo
Despite the implications for the development of life-history traits, endocrine-immune trade-offs in apes are not well studied. This is due, in part, to difficulty in sampling wild primates, and lack of methods available for immune measures using samples collected noninvasively. Evidence for androgen-mediated immune trade-offs in orangutans is virtually absent, and very little is known regarding their pattern of adrenal development and production …
Human sickness behavior
Sickness behavior, a coordinated set of behavioral changes in response to infection, lies at the intersection of immunology, endocrinology, and evolutionary biology. Sickness behavior is elicited by pro‐inflammatory cytokines, is thought to be an adaptive means of redirecting energy away from disadvantageous behaviors and toward mounting an effective immune response, and may be modulated by hormones, including testosterone and oxytocin. Research …
Disease and Human/Animal Interactions
Understanding pathogen exchange among human, wildlife, and livestock populations, and the varying ecological and cultural contexts in which this exchange takes place, is a major challenge. The present review contextualizes the risk factors that result from human interactions with livestock, companion animals, animal exhibits, wildlife through nature-based tourism, and wildlife through consumption. Given their phylogenetic relatedness to humans, p…
Primates on display
Human interactions with nonhuman primates vary tremendously, from daily cultural engagements and food commodities, to pet ownership and tourist encounters. These interactions provide opportunities for the exchange of pathogenic organisms (both zoonoses and anthroponoses). As exposures are not limited to areas where bushmeat usage continues to be a major problem, we must work to understand better our motivations for engaging in activities like own…
Short‐term resource allocation during extensive athletic competition
OBJECTIVES: Following predictions from life history theory, we sought to identify acute trade-offs between reproductive effort (as measured by psychological arousal) and somatic maintenance (via functional measures of innate immunity) during conditions of severe energetic imbalance. METHODS: Sixty-six male ultramarathon runners (ages 20 to 37 years) were sampled before and after a lengthy race. Saliva and sera were collected for testosterone and …
Religiosity/Spirituality and Physiological Markers of Health
Biology (21 obras) · Medicine (20 obras) · Immunology (15 obras) · Endocrinology (14 obras) · Ecology (12 obras) · Immune system (11 obras) · Internal Medicine (11 obras) · Psychology (11 obras) · Hormone (10 obras) · Primate Behavior and Ecology (10 obras)