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We report the rational engineering of a remarkably stable yellow fluorescent protein (YFP), 'hyperfolder YFP' (hfYFP), that withstands chaotropic conditions that denature most biological structures within seconds, including superfolder green fluorescent protein (GFP). hfYFP contains no cysteines, is chloride insensitive and tolerates aldehyde and osmium tetroxide fixation better than common fluorescent proteins, enabling its use in expansion and electron microscopies. We solved crystal structures of hfYFP (to 1.7-Å resolution), a monomeric variant, monomeric hyperfolder YFP (1.6 Å) and an mGreenLantern mutant (1.2 Å), and then rationally engineered highly stable 405-nm-excitable GFPs, large Stokes shift (LSS) monomeric GFP (LSSmGFP) and LSSA12 from these structures. Lastly, we directly exploited the chemical stability of hfYFP and LSSmGFP by devising a fluorescence-assisted protein purification strategy enabling all steps of denaturing affinity chromatography to be visualized using ultraviolet or blue light. hfYFP and LSSmGFP represent a new generation of robustly stable fluorescent proteins developed for advanced biotechnological applications.

Despite agreement that humans have evolved to be unusually fat primates, adipose patterning among hunter–gatherers has received little empirical consideration. Here we consider the development of adiposity among four contemporary groups of hunter–gatherers, the Aka, Savanna Pumé, Ju'/Hoansi and Agta using multi-level generalized additive mixed modelling to characterize the growth of tricep skinfolds from early childhood through adolescence. In contrast to references, hunter–gatherers show several consistent patterns: (i) children are lean with little fat accumulation; (ii) no adiposity rebound at 5 years is evident; (iii) girls on average have built 90% of their body size, and reach menarche when adiposity is at its maximum velocity; and (iv) a metabolic trade-off is evident in young, but not older children, such that both boys and girls prioritize skeletal growth during middle childhood, a trade-off that diminishes during adolescence when height velocity increases in pace with fat accumulation. Consistent results across hunter–gatherers living in diverse environments suggest that these patterns reflect a general forager pattern of development. The findings provide a valuable baseline for adipose development not apparent from reference populations. We emphasize both generalized trends among hunter–gatherers, and that inter-populational differences point to the plasticity with which humans organize growth and development. [ABSTRACT FROM AUTHOR]

A 60-year-old female presented with a large, left upper eyelid mass that had rapidly expanded in the 3 months prior to presentation. She had a presumed chalazion excised from the same area 1.5 years ago, but no pathology was investigated. On examination, she had a palpebral mass measuring 4.5 cm x 3.5 cm that abutted the globe with extensive conjunctival involvement. Neuroimaging demonstrated lesions concerning for parotid gland metastases. An incisional biopsy demonstrated synaptophysin-positive small blue cells concerning for neuroendocrine carcinoma. The patient underwent orbital exenteration with parotidectomy and radical neck dissection. The excised mass was found to have distinct neuroendocrine carcinoma cells intermingled with sebaceous carcinoma cells, a combination not previously reported. [ABSTRACT FROM AUTHOR]

Objective: Humans are unusually sexually dimorphic in body composition, with adult females having on average nearly twice the fat mass as males. The development of adipose sex differences has been well characterized for children growing up in food‐abundant environments, with less known about cross‐cultural variation, particularly in populations without exposure to market foods, mechanized technologies, schooling, vaccination, or other medical interventions. Methods: To add to the existing cross‐cultural data, we fit multiple growth curves to body composition and anthropometric data to describe adipose development for the Savanna Pumé, South American hunter‐gatherers. Results: (1) Little evidence is found for an adiposity 'rebound' at the end of early childhood among either Savanna Pumé girls or boys. (2) Rather, fat deposition fluctuates during childhood, from age ~4 to ~9 years, with no appreciable accumulation until the onset of puberty, a pattern also observed among Congo Baka hunter‐gatherers. (3) Body fat fluctuations are more pronounced for girls than boys. (4) The age of peak skeletal, weight, and adipose gains are staggered to a much greater extent among the Savanna Pumé compared to the National Health and Nutrition Examination Survey (NHANES III) reference, suggesting this is an important developmental strategy in lean populations. Conclusion: Documenting growth patterns under diverse preindustrial energetic conditions provides an important baseline for understanding sex differences in body fat emerging today under food abundance. [ABSTRACT FROM AUTHOR]

The Turkana, like other East African pastoral groups, are known for their tall adult stature, achieved despite a blunted growth spurt during adolescence and continued growth into the early 20s. To investigate the hormonal mechanisms associated with the pattern of slow and continued adolescent growth, we collected data on hormonal status, height, weight, and trunk skin-folds and ethnographic self-reports of testicular maturation in a cross-sectional sample of 35 nomadic and 37 settled Turkana males aged 14-24. Hormonal determinations included testosterone (T), sex hormone-binding globulin (SHBG), and dehydroepiandrosterone (DHEA) in blood, in addition to urinary DHEA. Self-reports of testicular maturation showed no difference between settled and nomadic subpopulations. However, nomadic boys exhibited significantly higher levels ofT, DHEA, and SHBG. Of all the hormones, only SHBG showed a significant relationship with age. Multiple regression models show blood T and SHBG to be significant independent predictors of achieved height as well as weight, controlling for age. Our results suggest that onset of puberty is substantially delayed among Turkana males, and that bioavailable T is related to growth in stature during adolescence. We suggest that SHBG acts to mediate the effects of energy availability on adolescent growth in this energetically limited population. Our findings may also have implications for understanding adolescent growth among Homo erectus. KEY WORDS adolescent growth; steroid hormones; East African pastoralists

Measures of cortisol and body composition were obtained from a sample of Turkana men to determine the role of cortisol in modulating the effects on muscle mass in a substance society. The results suggested that even in chronically undernourished populations, cortisol may be elevated primarily under conditions of acute nutritional stress.

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 role of seasonality in species differences among nonhuman primates, we compared leptin, testosterone, and body composition in male rhesus (n = 69) and pig-tailed (n = 43) macaques. Despite having larger abdominal fat deposits, the rhesus macaques did not exhibit significantly higher leptin levels (rhesus, 2.21 [+ or -] 0.43 ng/ ml; pig-tailed, 2.12 [+ or -] 0.39 ng/ml). Both species showed increases in leptin across adolescent, subadult, and adult age-groups (P = 0.036 for rhesus; P = 0.0003 for pig-tailed by ANCOVA). Testosterone was not significantly associated with leptin in either the rhesus (r = 0.039; P = 0.754) or pig-tailed (r = 0.2862; P = 0.066) samples. Comparison of leptin levels across the two species using univariate modeling procedures showed no significant age-group by abdominal fat interaction. These findings suggest little difference in leptin production between these two closely related species, despite the difference in breeding seasonality. KEY WORDS adiposity; energetics; primate mass index; Macaca mulatta; Macaca nemestrina; contest competition

To test attitudes toward male body image in a society with relatively little media exposure, the authors surveyed 53 men, ages 20-35, among the Ariaal, pastoral nomads of northern Kenya. Measures of body image were obtained using a somatomorphic matrix. Height, weight, and percentage of body fat based on bioelectric impedance were also obtained. Results indicate that men exhibit very little discrepancy between what they perceive as the degree of muscularity preferred by women and that of the average man (.21 kg/[m.sup.2]). Comparison with findings from the United States and Western Europe indicates that Ariaal men show significantly less discrepancy between their judgment of women's preference for muscularity and the muscularity of the average man. These results support a role for media exposure in attitudes about male body image. Keywords: male body image; Africa; pastoral nomads

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, testosterone, and estradiol levels, but differed substantially in testicular volume (3.00 [+ or -] 1.7 vs. 1.72 [+ or -] 1.3 cc), abdominal skinfold measures (15.7 [+ or -] 9.2 vs. 9.0 [+ or -] 7.7 mm), and DHEA-S levels (18.0 [+ or -] 11.7 vs. 7.6 [+ or -] 5.4 [micro]g/dl). Significant interaction effects for species by age group were found for weight, tricep circumference, length, and estradiol level. In addition, length was more closely related to testicular volume among rhesus compared to pig-tailed macaques, suggesting different developmental patterns between the species. Predictors of hormonal levels differed between the two species. In the rhesus, estradiol levels were related to testicular volume and testosterone levels while there were no anthropometric predictors of testosterone or DHEA-S. For the pigtailed macaques, testicular volume was related to tricep circumference, testosterone to triceps skinfold and testicular volume, and estradiol to weight. It is argued that rhesus have larger testes for body size and more abdominal fat deposits during the early breeding season relative to pig-tailed macaques reflecting the increased demands of sperm competition in a seasonally breeding species. Hormonal differences associated with the difference in breeding system appear to be primarily related to adrenal rather than testicular activity. Am J Phys Anthropol 117:218-227, 2002. KEY WORDS sperm competition; primates; male reproductive biology; body composition