Understanding muscle markers: lower limbs

Musculoskeletal markers are frequently used to reconstruct past lifestyles and activity patterns. Yet the reliability of muscle marker measurements has been called into question because they may be confounded by body size. In this study, an aggregate muscle marker variable was calculated using 20 insertion sites (14 femoral, 6 tibial), and I examined their effects on lower limb size (as a proxy for body size), age, and sex. Analyses were made of a sample of 77 (57 males, 20 females) Native British Columbians (3,500-1,500 years BP) and 18th century Quebec prisoners. Muscle markers were measured using two-point observer rating scales; size was measured by standard methods; and age and sex were determined through pelvic, cranial, and dental morphology. Lower limb muscle markers correlated with: age, r=0.61; lower limb size, r=0.52; and sex, r=0.49; P <0.001. Older individuals had higher muscle marker scores, as did larger individuals and males. Based on partial correlations and regression analyses, age was the best overall predictor of lower limb muscle markers.     

Muscle markers revisited: activity pattern reconstruction with controls in a central California Amerind population

Anthropologists frequently use musculoskeletal stress markers to reconstruct past activity patterns. Yet, researchers have called into question the reliability of muscle marker measurements in part because body size and age affect muscle marker scores. In this study, the author examined an aggregate upper limb muscle marker to determine if after controlling for the effects of body size and age, one could reconstruct activity patterns of a prehistoric Amerind population. Analyses were made of a sample of 102 (43 males, 59 females) prehistoric central California Amerinds. Muscle markers were measured using two-point observer rating scales; body size was measured by humeral articular surfaces; age and sex were determined previously through standard procedures. Using sex separated rankings and partial correlations, disaggregated muscle markers were examined for correlations with age and size to determine if specific muscle markers may be useful in pinpointing to activity patterns. Aggregate upper limb muscle marker correlated with: age, r = 0.44; humeral size, r = 0.44; and sex, r = 0.43; Ps < 0.001. Older individuals had greater muscle markers, as did larger individuals, and males. Rankings seemed to be confounded by the effect size had on the muscle markers. However, based on partial correlations controlling for size and age, the differences that remained between males and females could be used to reconstruct male activities of throwing in hunting and interpersonal aggression acts.     

Enthesopathies as occupational stress markers: Evidence from the upper limb

Enthesopathies—that is, “musculo‐skeletal stress markers”—are frequently used to reconstruct past lifestyles and activity patterns. Relatively little attention has been paid in physical anthropology to methodological gaps implicit in this approach: almost all methods previously employed neglect current medical insights into enthesopathies and the distinction between healthy and pathological aspects has been arbitrary. This study presents a new visual method of studying fibrocartilaginous enthesopathies of the upper limb (modified from Villotte: Bull Mém Soc Anthropol Paris n.s. 18 (2006) 65–85), and application of this method to 367 males who died between the 18th and 20th centuries, from four European identified skeletal collections: the Christ Church Spitalfields Collection, the identified skeletal collection of the anthropological museum of the University of Coimbra, and the Sassari and Bologna collections of the museum of Anthropology, University of Bologna. The analysis, using generalized estimating equations to model repeated binary outcome variables, has established a strong link between enthesopathies and physical activity: men with occupations involving heavy manual tasks have significantly (P‐value < 0.001) more lesions of the upper limbs than nonmanual and light manual workers. Probability of the presence of an enthesopathy also increases with age and is higher for the right side compared with the left. Our study failed to distinguish significant differences between the collections when adjusted for the other effects. It appears that enthesopathies can be used to reconstruct past lifestyles of populations if physical anthropologists: 1) pay attention to the choice of entheses in their studies and 2) use appropriate methods. Am J Phys Anthropol, 2010. © 2009 Wiley‐Liss, Inc.     

Musculoskeletal stress markers in Natufian hunter-gatherers and Neolithic farmers in the Levant: the upper limb

This paper attempts to quantify the changes in activity patterns of early farming populations in the Levant through the musculoskeletal stress markers (MSM) of the upper limb as seen in skeletal remains. The transition to an agricultural way of life resulted in higher loads on the upper limb in Neolithic populations compared to the Natufian hunter-gatherer populations that preceded them. The MSM pattern for males and females indicates a gender-based division of labor both in the Natufian and the Neolithic. It may also suggest that people in the Neolithic period were engaged in different (new) activities and occupations compared to the Natufian.     

Elucidating inequality in Nubia: An examination of entheseal changes at Kerma (Sudan)

Located 10 km south of the Third Cataract of the Nile River, the ancient city of Kerma was once capital to the second largest state in Africa. The Eastern Cemetery at Kerma (～4 km east of city center) encompasses 80+ hectares and was used over a period of 1,500 years (3,200–1,500 BC). Excavated in the early 20th century by George Reisner, the cemetery contained an estimated 20,000–40,000 individuals. Reisner classified these burials into multiple categories, including chiefs and human sacrifices, based on burial position and grave goods. This study investigates the skeletal embodiment of social inequality by examining variation in entheseal severity between the Kerma burial classifications. Seventeen entheses were examined using the Hawkey and Merbs (1995) scoring method (n = 205 individuals); age, sex, and body size variables were considered by employing Mann–Whitney U tests and partial Spearman's correlations. This analysis suggests that significant differences in entheseal changes existed between select burial types. Specifically, “corridor sacrifices” had significantly higher rates of entheseal changes while “chiefs” and “subsidiary burials” had similar entheseal changes; furthermore, within these burial categories, males had higher entheseal scores despite body size controls. The elevated entheseal changes in the sacrificial burials may be due to an intensive agro‐pastoral lifestyle or other demanding forms of manual labor. In conclusion, the disparity of entheseal markers between burial subgroups at Kerma might reflect a degree of social inequality within this state level society. This bioarchaeological research informs our understanding of socially‐defined categories of persons as well as everyday life in Ancient Kerma. Am J Phys Anthropol 156:192–202, 2015. © 2014 Wiley Periodicals, Inc.     

Activity patterns in New Kingdom Nubia: An examination of entheseal remodeling and osteoarthritis at Tombos

The effects of Egyptian imperial expansion into Nubia during the New Kingdom Period (1,550–1,069 BC) have been debated. Here, the impacts of the Egyptian Empire are investigated through an examination of osteological indicators of activity at the archaeological site of Tombos. Entheseal changes to fibrocartilaginous attachment sites and osteoarthritis are examined to infer what types of physical activities this colonial town was engaging in. Many of the skeletal remains at Tombos were comingled due to looting in antiquity; undisturbed burials are presented as a subsample of the population (n = 28) in which age, sex, and body size can be considered. The total sample (n = 85) is then analyzed to better understand overall levels of activity. A number of Nile River Valley bioarchaeological samples are used as points of comparison to the Tombos population. Results indicate that the inhabitants of Tombos had relatively low entheseal remodeling scores; this is highlighted when Tombos is juxtaposed with comparative samples, particularly in men. Furthermore, osteoarthritis, as assessed by eburnation, was also markedly infrequent at Tombos. Collectively, these results indicate a relatively low level of activity and support the hypothesis that Tombos may have served as an administrative center. Am J Phys Anthropol, 2012. © 2012 Wiley Periodicals, Inc.     

Upper limb musculoskeletal stress markers among middle Holocene foragers of Siberia's Cis‐Baikal region

This evaluation of musculoskeletal stress markers (MSMs) in the Cis‐Baikal focuses on upper limb activity reconstruction among the region's middle Holocene foragers, particularly as it pertains to adaptation and cultural change. The five cemetery populations investigated represent two discrete groups separated by an 800–1,000 year hiatus: the Early Neolithic (8000–7000/6800 cal. BP) Kitoi culture and the Late Neolithic/Bronze Age (6000/5800–4000 cal. BP) Isakovo‐Serovo‐Glaskovo (ISG) cultural complex. Twenty‐four upper limb MSMs are investigated not only to gain a better understanding of activity throughout the middle Holocene, but also to independently assess the relative distinctiveness of Kitoi and ISG adaptive regimes. Results reveal higher heterogeneity in overall activity levels among Early Neolithic populations—with Kitoi males exhibiting more pronounced upper limb MSMs than both contemporary females and ISG males—but relative constancy during the Late Neolithic/Bronze Age, regardless of sex or possible status. On the other hand, activity patterns seem to have varied more during the latter period, with the supinator being ranked high among the ISG, but not the Kitoi, and forearm flexors and extensors being ranked generally low only among ISG females. Upper limb rank patterning does not distinguish Early Neolithic males, suggesting that their higher MSM scores reflect differences in the degree (intensity and/or duration), rather than the type, of activity employed. Finally, for both Kitoi and ISG peoples, activity patterns—especially the consistently high‐ranked costoclavicular ligament and deltoid and pectoralis major muscles—appear to be consistent with watercraft use. Am J Phys Anthropol, 2009. © 2008 Wiley‐Liss, Inc.     

Enthesopathy formation in the humerus: Data from known age‐at‐death and known occupation skeletal collections

Enthesopathies, in the guise of musculoskeletal skeletal stress markers (MSM), have been widely used to reconstruct activity levels in human skeletal populations. In general, studies have focused on their presence in the upper limb, which is used in the majority of daily activities. The aim of this study was to use some of the attachment sites on the humerus to explore the relationship between enthesopathy formation, activity, and the ageing process. The skeletal sample used in this study comprised male adult skeletons with known age‐at‐death and known occupations from the late‐19th and early‐20th century cemeteries in Portugal. The enthesopathies were recorded as either present or absent. Statistical analysis using Fishers exact tests and logistic regression was undertaken to determine whether associations could be found between specific activities or socioeconomic status (manual or nonmanual workers), and age and enthesopathy presence. Left and right sides were analyzed separately. Fisher's exact tests were used to determine the relationship between activity and enthesopathy, and they demonstrated no association between activity and enthesopathies (P > 0.01). The results of the logistic regression established that age was the single most significant factor in enthesopathy formation (P > 0.05). This study found that, in these samples, age‐at‐death, and therefore age‐related degeneration rather than degeneration caused by activities, was the primary cause of enthesopathy formation. Considering the difficulties of reliably ageing adult human skeletal remains, this is a major issue for studies of activity using enthesopathies. Am J Phys Anthropol, 2010. © 2009 Wiley‐Liss, Inc.     

Tracing prehistoric activities: musculoskeletal stress marker analysis of a Stone-Age population on the island of Gotland in the Baltic sea

The skeletal remains from the Middle Neolithic (2750-2300 BC) burial ground at Ajvide, Gotland, are analyzed in order to explore musculoskeletal patterns and to attempt to trace general as well as three specific prehistoric activities (archery, harpooning, and kayaking) that are likely to have been performed in this marine setting of fishing, hunting, and gathering. Scoring of muscular and ligament attachments is performed using the scoring method of Hawkey and Merbs ([1995] Int. J. Osteoarchaeol. 5:324-338) for muskuloskeletal stress markers (MSM). The skeletal material consists of 24 male and 15 female adult individuals divided into three age groups: young (<24 years), middle (25-39 years), and old (>40 years). Thirty upper body MSM sites, on both the left and right sides, are scored and form the basis of the study. Results show that males most frequently have higher mean MSM scores than females. Bilateral asymmetry was noted as low in both sexes. Age proved to be a contributing factor to increased MSM scores, with a greater age-related increase in females. MSM patterns were analyzed statistically in muscle groups associated with the three investigated activities. Significant positive correlations were observed in male individuals in muscle groups associated with archery and to some extent harpooning, an indication that these activities would mainly have been performed by men. Correlations in kayaking muscles were not evidently consistent with the kayaking motion. Furthermore, the costoclavicular ligament, often referred to in connection with "kayaker's clavicle," showed no positive statistical correlation with the kayaking muscles.     

Identification of sex chromosome molecular markers using RAPDs and fluorescent in situ hybridization in rainbow trout

The goal of this work is to identify molecular markers associated with the sex chromosomes in rainbow trout to study the mode of sex determination mechanisms in this species. Using the RAPD assay and bulked segregant analysis, two markers were identified that generated polymorphic bands amplifying preferentially in males of the Mount Lassen and Scottish strains of rainbow trout. Chromosomal localization using fluorescent in situ hybridization of a 900 bp probe developed from one of these markers revealed a brightly defined signal on a chromosome that could morphologically be classified as the Y chromosome. This revised version was published online in July 2006 with corrections to the Cover Date.     

Functional plasticity of the human humerus: Shape,rigidity, and muscular entheses

The relationship between the mechanical loading undergone by a bone and its form has been widely assumed as a premise in studies aiming to reconstruct behavioral patterns from skeletal remains. Nevertheless, this relationship is complex due to the existence of many factors affecting bone structure and form, and further research combining structural and shape characteristics is needed. Using two‐block PLS, which is a test to analyze the covariance between two sets of variables, we aim to investigate the relationship between upper‐limb entheseal changes, cross‐sectional properties, and contour shape of the humeral diaphysis. Our results show that individuals with strongly marked entheseal changes have increased diaphyseal rigidities. Bending rigidities are mainly related to entheseal changes of muscles that cross the shoulder. Moreover, the entheseal changes of muscles that participate in the rotation of the arm are related to mediolaterally flatter and ventrodorsally broader humeral shapes in the mid‐proximal diaphysis. In turn, this diaphyseal shape is related to diaphyseal rigidity, especially to bending loadings. The shape of the diaphysis of the rest of the humerus does not covary either with rigidity or with entheseal changes. The results indicate that large muscular scars, such as those found in the mid‐proximal diaphyses, seem to be related to diaphyseal shape, whereas this relationship is not seen for areas with less direct influences of powerful muscles. Am J Phys Anthropol 150:609–617, 2013. © 2013 Wiley Periodicals, Inc.     

Spondylolysis of the sacrum in Alaskan and Canadian Inuit skeletons

Spondylolysis of the lower back, particularly that involving the isthmus between the superior and inferior articular processes (pars inter-articularis), is generally attributed to stress fracturing caused by movement of the affected vertebra relative to the vertebra below. The finding of isthmic spondylolysis in the first vertebra of a fused sacrum is thus unusual and requires explanation. Although unrepresented in the clinical literature, sacral spondylolysis has been reported for archaeological specimens and appears to be especially prevalent in North American Inuit. A study of 373 Inuit sacra from Alaska and Canada produced 16 examples of spondylolysis (eight from each area). All but one of the affected individuals were male, and nearly all were young adults, many between 18 and 20 years of age. All cases of sacral spondylolysis observed in this study were judged to have resulted from stress fracturing that occurred while S1 was still unfused, and most appear to have been in the process of healing, following fusion of S1 with S2, when death occurred. The high frequency observed in these people is attributed to unusual stresses becoming concentrated in the lower back of adolescent males due to such activities as weight lifting, wrestling, kayak paddling, and harpooning, combined with, and perhaps even contributing to, delayed maturation (S1-S2 fusion) of the sacrum. © 1996 Wiley-Liss, Inc.     

Immunoquantification of flavodoxin and ferredoxin from Scenedesmus vacuolatus (Chlorophyta) as iron-stress molecular markers

Quantification of the iron nutritional status of phytoplankton is of great interest not only for the study of the oceans but also for fresh waters. Flavodoxin is a small flavoprotein proposed as a molecular marker for iron stress, since it is induced as a consequence of iron deprivation, replacing the iron-sulphur protein ferredoxin. Flavodoxin and ferredoxin from Scenedesmus vacuolatus have been immunoquantified in cells grown under different iron nutritional conditions. Flavodoxin and ferredoxin levels correlate with the iron availability, and the calculated flavodoxin index can be used as an iron-stress marker. Other physiological parameters such as copper deficiency, heterotrophic or mixotrophic growth, nitrogen source and salt stress were also tested as potential factors influencing flavodoxin expression. Salt stress and heterotrophic growth conditions alter flavodoxin and ferredoxin expression. Once flavodoxin expression is repressed by iron (and severe deficiency alleviated), S.vacuolatus still increases its ferredoxin from 0·5 to 1·6 mol of ferredoxin per mole of ferredoxin-NADP⁺ reductase, and this ratio can be used for the evaluation of mild deficiency.     

Lower limb activity in the Cis‐Baikal: Entheseal changes among middle holocene siberian foragers

Lower limb entheseal changes are evaluated in order to reconstruct activity levels and more fully understand cultural and behavioral variation among the middle Holocene (ca. 9,000–3,000 years BP) foragers of Siberia's Cis‐Baikal region. The four cemetery samples examined span a period of diachronic change characterized by an 800‐ to 1,000‐year discontinuity in the use of formal cemeteries in the region. Two of the cemetery samples represent the early Neolithic Kitoi culture, dating from 8,000 to 7,000/6800 cal. BP; the other two represent the late Neolithic‐early Bronze Age Isakovo‐Serovo‐Glazkovo (ISG) cultural complex, dating from 6,000/5,800 to 4,000 cal. BP. Findings suggest a dynamic pattern of cultural variability in the Cis‐Baikal, with spatial distribution (i.e., site location within particular microregions) appearing to be just as important a factor as cultural/temporal affiliation in explaining intersample differences in entheseal morphology. In addition, intrasample comparisons reveal increasing sexual disparity with advancing age at death, emphasizing the influence of sex‐related activities on lower limb entheseal changes. Finally, results from the separate fibrous and fibrocartilaginous datasets appear to be largely congruous, implying that activity patterns in the Cis‐Baikal may have similar effects on the morphology of both types of entheses. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.     

Non-metric cranial traits: Sex difference and age dependence

Absence of association with age and/or sex in the case of discrete traits was hypothesized by Berry & Berry (1967). The important implication that skeletal material too fragmentary for sex and age determination may also be used in discrete-trait-studies stimulated us to test this hypothesis for 49 discrete traits in 254 Amsterdam crania of known age and sex. The results were compared with those of other such studies of European skulls. No significant deviation from the hypothesis was found as far as age dependence is concerned while sex difference did occur for some traits. At the same time Corruccini's (1974) conclusion that the hypothesis fails when tested in the Terry collection was found to result largely from the fact that right and left manifestations of lateral traits were treated as being independent. The possibility of including skeletal material too fragmentary for sex and age determination in future discrete-trait-studies is still open for discussion.     

Genetic validity of RAPD markers at the intra- and inter-specific level in wild Brassica species with n=9

The sequence homology of co-migrating RAPD markers within a genus, across species, and among populations of a species was investigated. DNA was isolated from ten wild Brassica species with n=9 and the RAPD patterns were established using three random primers. Five RAPD markers which appeared to be characteristic for the n=9 species (genus level), four markers which appeared to be species specific, and one population-specific marker were isolated from agarose gels and hybridized to the RAPD profiles of the ten Brassica species. Two RAPD markers were cloned for comparison with gel-isolated RAPD fragment probes in hybridization experiments. Non-specific and background hybridization, occurring when gel-isolated fragments were used as probes, disappeared when cloned fragments were used. A total of 250 RAPD-marker hybridizations were scored according to visual presence or absence in a gel lane. All except three markers hybridized as expected, resulting in an error rate of 1.2%. The deviating results included a lack of hybridization although a band was visible in the gel, a length polymorphism for one marker, and a dual hybridization signal for two single-band markers.     

Genetic alterations in medullary thyroid cancer: diagnostic and prognostic markers

Medullary thyroid carcinoma (MTC) is a rare calcitonin producing neuroendocrine tumour that originates from the parafollicular C-cells of the thyroid gland. The RET proto-oncogene encodes the RET receptor tyrosine kinase, with consequently essential roles in cell survival, differentiation and proliferation. Somatic or germline mutations of the RET gene play an important role in this neoplasm in development of sporadic and familial forms, respectively. Genetic diagnosis has an important role in differentiating sporadic from familiar MTC. Furthermore, depending on the location of the mutation, patients can be classified into risk classes. Therefore, genetic screening of the RET gene plays a critical role not only in diagnosis but also in assessing the prognosis and course of MTC.     

Rapid assessment of the sex of codling moth Cydia pomonella (Linnaeus) (Lepidoptera: Tortricidae) eggs and larvae

Two different methods were tested to identify the sex of the early developmental stages of the codling moth Cydia pomonella (Linnaeus) (Lepidoptera: Tortricidae) with a WZ/ZZ (female/male) sex chromosome system. First, it was shown that the sex of all larval stages can be easily determined by the presence or absence of sex chromatin, which is formed by the female‐specific W chromosome in interphase nuclei. This trait can also be used to identify the sex of newly hatched larvae but it does require care and accuracy. Secondly, a new sexing technique was developed based on a molecular marker of the codling moth W chromosome. Flanking regions of an earlier described W‐specific sequence (CpW2) were isolated and sequenced and a 2.74 kb sequence (CpW2‐EcoRI), specific for the W chromosome, was obtained. Several PCR tests were conducted, which confirmed that the CpW2‐EcoRI sequence is a reliable marker for the sex identification in codling moth samples of different geographical origin. In addition, a fragment of a codling moth gene, period (Cpper) was isolated and sequenced. Results of southern hybridization of the Cpper probe with female and male genomic DNA suggested that the Cpper gene is located on the Z chromosome. Then a multiplex PCR assay was developed, which co‐amplified the CpW2‐EcoRI sequence to identify the W chromosome and the Z‐linked Cpper sequence, which served as a positive control of accurate processing of tested samples. The multiplex PCR provides an easy and rapid identification of the sex of embryos and early larval instars of the codling moth.     

Enzyme markers in inbred rat strains: Genetics of new markers and strain profiles

Twenty-six inbred strains of the laboratory rat (Rattus norvegicus) were examined for electrophoretic variation at an estimated 97 genetic loci. In addition to previously documented markers, variation was observed for the enzymes aconitase, aldehyde dehydrogenase, and alkaline phosphatase. The genetic basis of these markers (Acon-1, Ahd-2, and Akp-1) was confirmed. Linkage analysis between 35 pairwise comparisons revealed that the markers Fh-1 and Pep-3 are linked. The strain profiles of the 25 inbred strains at 11 electrophoretic markers are given.