Sex differences in activity-related osseous change in the spine and the gendered division of labor at Ensay and Wharram Percy, UK

Sex differences in the distribution of vertebral degenerative and plastic change were examined and compared within and between samples of 51 individuals from the historically and ethnographically documented 16th-19th century site of Ensay, the Outer Hebrides, and 59 individuals from the medieval site of Wharram Percy, the Yorkshire Wolds. Both populations have a known gendered division of labor between males and females and known activity-related stresses on the spine. Osseous changes normally associated with degenerative joint disease (osteoarthritis) of the apophyseal facets and osteophytosis of the vertebral bodies were scored and reported separately. Inter- and intrasite differences were found in the frequency and distribution of osseous change down the spine. Overall, the Ensay sample was more highly stressed than that from Wharram Percy. Furthermore, differences between males and females at Ensay could be identified as relating to different types of activities. Distinctions between males and females at Wharram Percy were less marked, suggesting broadly similar lifestyles. These results accorded with expectations regarding contrasting levels of activity-related stress at the two sites and the division of labor between males and females. In particular, the prevalence and distribution of facet remodeling, facet sclerosis/eburnation, and osteophytosis in Ensay females could be related to load-bearing using creels (a form of basket), which disrupted "normal" patterns of osseous change along the spine. Importantly, morphologically distinct osseous modifications recorded on the apophyseal facets produced dissimilar distributions, suggesting that they may have different etiologies. These results highlight the need for a high degree of discrimination in recording, analyzing, and exploring activity-related osseous change.     

Medieval trabecular bone architecture: the influence of age, sex, and lifestyle

Osteoporosis has become a growing health concern in developed countries and an extensive area of research in skeletal biology. Despite numerous paleopathological studies of bone mass, few studies have measured bone quality in past populations. In order to examine age- and sex-related changes in one aspect of bone quality in the past, a study was made of trabecular bone architecture in a British medieval skeletal sample. X-ray images of 5-mm-thick coronal lumbar vertebral bone sections were taken from a total of 54 adult individuals divided into three age categories (18-29, 30-49, and 50+ years), and examined using image analysis to evaluate parameters related to trabecular bone structure and connectivity. Significant age-related changes in trabecular bone structure (trabecular bone volume (BV/TV), trabecular number (Tb.N), trabecular separation (Tb.Sp), and anisotropic ratio (Tb.An)) were observed to occur primarily by middle age with significant differences between the youngest and two older age groups. Neither sex showed continuing change in trabecular structure between the middle and old age groups. Age-related changes in bone connectivity (number of nodes (N.Nd) and node-to-node strut length (Nd.Nd)) similarly indicated a change in bone connectivity only between the youngest and two older age groups. However, females showed no statistical differences among the age groups in bone connectivity. These patterns of trabecular bone loss and fragility contrast with those generally found in modern populations that typically report continuing loss of bone structure and connectivity between middle and old age, and suggest greater loss in females. The patterns of bone loss in the archaeological samples must be interpreted cautiously. We speculate that while nutritional factors may have initiated some bone loss in both sexes, physical activity could have conserved bone architecture in old age in both sexes, and reproductive factors such as high parity and extended periods of lactation could have played a key role in female bone maintenance in this historic population. The study of qualitative elements (such as trabecular architecture) is vital if we are to understand bone maintenance and fragility in the past.     

Osteoporosis in a population from medieval Norway

Modern populations from Norway and England differ in their experience of osteoporosis, the former showing lower bone mineral density (BMD) and a higher fragility fracture rate. The aim of the present work was to investigate whether this was also the case during the Middle Ages. Age-dependent loss of BMD in the proximal femur was assessed using dual X-ray absorptiometry (DXA) in male and female adult skeletons from a cemetery in the medieval town of Trondheim, Norway. Fracture prevalence was also investigated. Results were compared with those previously reported for a skeletal series from Wharram Percy, a deserted medieval village in England. Results indicate that peak BMD and patterns of age-related loss of BMD in the Norwegian and the English group were similar. Among females, the prevalence of osteoporotic fractures was greater in the Norwegian than in the English population. The BMD results suggest that differences in BMD between English and Norwegians are of recent origin, although given the fairly modest sample sizes, further work is needed to confirm this. Reasons for the greater prevalence of osteoporotic fractures in women in the Norwegian skeletal series are unclear, but the colder climate and greater frequency of hard surfaces may have meant that falls were more frequent, and when they occurred, were more likely to result in fractures than in the rural English group.     

Lumbar vertebral morphology and isthmic spondylolysis in a British medieval population

The British medieval population from Wharram Percy, England, has a greater prevalence of isthmic spondylolysis (11.9% of skeletons, 8.5% at the L5 level) than in modern populations (3%–6%). This may in part be due to differences in activity patterns between groups. However, Ward and Latimer (Spine 30 [2005] 1808–1814) proposed that the likelihood of developing and maintaining spondylolytic defects is also influenced by a lack of sufficient increase in mediolateral separation between articular processes in the lowest lumbar segments, given the human lumbar lordosis. Here, we demonstrate that spondylolytic individuals from Wharram Percy tend to have a less pronounced difference between mediolateral facet joint spacing of adjacent segments in the lowest lumbar region than do unaffected individuals, as seen in modern clinical and skeletal populations. These comparisons suggest that regardless of lifestyle, insufficient mediolateral increase in facet spacing predisposes people to spondylolytic defects, and so interfacet spacing patterns may have predictive utility in a clinical context. We also compare the Wharram Percy sample to a modern sample from the Hamann Todd collection with a typically modern prevalence rate. Data do not support the hypothesis that the Wharram Percy individuals had a less pronounced interfacet increase than the Hamann Todd, although they do have narrower lumbar facet spacing at the lowest three levels. Further investigation of anatomical variation underlying population‐specific prevalence rates needs to be conducted. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.     

Bone mineral density, osteopenia, and osteoporosis in the rhesus macaques of Cayo Santiago

This cross-sectional study investigates metabolic bone disease and the relationship between age and bone mineral density (BMD) in males and females of a large, well-documented skeletal population of free-ranging rhesus monkeys (Macaca mulatta), from the Caribbean Primate Research Center Museum collection from Cayo Santiago, Puerto Rico. The sample consists of 254 individuals aged 1.0-20+ years. The data consist of measurements of bone mineral content and bone mineral density, obtained from dual-energy X-ray absorptiometry (DEXA), of the last lumbar vertebra from each monkey. The pattern of BMD differs between male and female rhesus macaques. Females exhibit an initial increase in BMD with age, with peak bone density occurring around age 9.5 years, and remaining constant until 17.2 years, after which there is a steady decline in BMD. Males acquire bone mass at a faster rate, and attain a higher peak BMD at an earlier age than do females, at around 7 years of age, and BMD remains relatively constant between ages 7-18.5 years. After age 7 there is no apparent effect of age on BMD in the males of this sample; males older than 18.5 years were excluded due to the presence of vertebral osteophytosis, which interferes with DEXA. The combined frequency of osteopenia and osteoporosis in this population is 12.4%. BMD values of monkeys with vertebral wedge fractures are generally higher than those of virtually all of the nonfractured osteopenic/osteoporotic individuals, thus supporting the view that BMD as measured by DEXA is a useful but imperfect predictor of fracture risk, and that low BMD may not always precede fractures in vertebral bones. Other factors such as bone quality (i.e., trabecular connectivity) should also be considered. The skeletal integrity of a vertebra may be compromised by the loss of key trabeculae, resulting in structural failure, but the spine may still show a BMD value within normal limits, or within the range of osteopenia.     

Noninvasive estimation of bone mass in ancient vertebrae

Histomorphometry is useful in the assessment of trabecular bone mass (TBM), and thus, in the estimation of the prevalence and intensity of osteopenia in ancient population groups. However, it is a destructive method. It is therefore necessary to explore the accuracy of nondestructive approaches, such as radiography, bone mineral density (BMD) assessed by double-energy X-ray absorptiometry (DEXA), bone density (BD), or optical density (OD) in the diagnosis of osteopenia. We selected 51 vertebrae out of a total sample composed of 333 T12, L1, and L2 vertebrae belonging to adult pre-Hispanic inhabitants from El Hierro. These vertebrae underwent histomorphometrical analysis, a fine-grained film radiography with assessment of trabecular pattern following standard methods, OD, DEXA-assessed BMD, and BD. The presence of biconcave vertebrae and wedge-shaped vertebrae was also assessed by measuring anterior height (a), posterior height (p), and height at the middle point of the vertebral body (m), and further calculating the indices 2m/(a + p) ("spine score") and a/p. Significant correlations were observed between TBM and BMD (r=0.43), TBM and BD (r=0.49), TBM and OD (r=0.52), BMD and OD (r=0.51), and BMD and BD (r=0.36), but not between TBM and the indices 2m/(a + p) and a/p. In the stepwise multiple correlation analysis between TBM and BMD, BD, and OD, OD entered into first place and BD into second place, whereas BMD became displaced; the multiple correlation coefficient was 0.63, with a standard error of 3.78. A BMD greater than 0.60 g/cm2, or a bone density greater than 0.60 g/cm3, excluded osteopenia (TBM <15%) with a specificity greater than 90%, whereas a BMD value less than 0.35 g/cm2, a BD less than 0.35 g/cm3, or optical density >1.6 excluded a normal bone mass (TBM >20%) with a specificity greater than 90%. Based on radiographic criteria on the total sample, we also conclude that the overall prevalence of vertebral fractures in the adult pre-Hispanic population of El Hierro of any age is 7.5%.     

Vertebral Bone Marrow Fat Is Positively Associated With Visceral Fat and Inversely Associated With IGF‐1 in Obese Women

Recent studies have demonstrated an important physiologic link between bone and fat. Bone and fat cells arise from the same mesenchymal precursor cell within bone marrow, capable of differentiation into adipocytes or osteoblasts. Increased BMI appears to protect against osteoporosis. However, recent studies have suggested detrimental effects of visceral fat on bone health. Increased visceral fat may also be associated with decreased growth hormone (GH) and insulin‐like growth factor 1 (IGF‐1) levels which are important for maintenance of bone homeostasis. The purpose of our study was to assess the relationship between vertebral bone marrow fat and trabecular bone mineral density (BMD), abdominal fat depots, GH and IGF‐1 in premenopausal women with obesity. We studied 47 premenopausal women of various BMI (range: 18–41 kg/m², mean 30 ± 7 kg/m²) who underwent vertebral bone marrow fat measurement with proton magnetic resonance spectroscopy (1H‐MRS), body composition, and trabecular BMD measurement with computed tomography (CT), and GH and IGF‐1 levels. Women with high visceral fat had higher bone marrow fat than women with low visceral fat. There was a positive correlation between bone marrow fat and visceral fat, independent of BMD. There was an inverse association between vertebral bone marrow fat and trabecular BMD. Vertebral bone marrow fat was also inversely associated with IGF‐1, independent of visceral fat. Our study showed that vertebral bone marrow fat is positively associated with visceral fat and inversely associated with IGF‐1 and BMD. This suggests that the detrimental effect of visceral fat on bone health may be mediated in part by IGF‐1 as an important regulator of the fat and bone lineage.     

Bone loss in the ovariectomized baboon Papio ursinus: densitometry, histomorphometry and biochemistry

To develop a non-human primate model of systemic bone loss after ovariectomy, 24 ovariectomized (OVX) and eight control (non-OVX) female baboons Papio ursinus were investigated over a period of 48 months using bone mineral density (BMD), iliac crest bone histomorphometry, bone turnover markers, and variables of calcium metabolism. Lumbar spine (L1-L4) BMD measured by dual energy X-ray absorptiometry (DXA) decreased in OVX animals in the first 12 months (-7.6%) and showed a slow trend towards recovery after 24 months. Controls showed a slow increase in spinal BMD over 4 years (+9.7%). Total hip BMD decreased slowly up to 48 months in all animals (OVX -12.6%versus controls -10%); this indicated that OVX had a limited effect on total hip BMD. Forearm BMD did not change. The significant decrease in trabecular bone volume (TBV) of the iliac crest from baseline to 12 months was followed by some recovery. Microarchitectural deterioration of trabecular bone in OVX animals was demonstrated by a decline in trabecular number and an increase in trabecular spacing. These changes were also evident on sections of whole vertebrae, proximal femora and iliac crests. Changes in iliac TBV reflected spinal but not hip BMD changes in the OVX animals. Static and dynamic histomorphometric variables indicated that bone turnover was increased for 36 months following OVX. Controls showed no changes in histomorphometric variables. Bone specific alkaline phosphatase (ALPs) in OVX animals remained elevated throughout the study; osteocalcin (OC) was significantly elevated only at 6 and 12 months, and deoxypyridinoline (Pyr-D) was elevated at 12 months but declined after 24 months. ALPs was thus more sensitive to the long-term effects of OVX than were OC or Pyr-D. Controls showed no changes in bone turnover markers. This study showed consistent deleterious changes in lumbar BMD, bone histomorphometry with microarchitectural deterioration together with altered biochemical markers of bone turnover in the first 12 months after OVX. Since these changes resemble those in post-menopausal women, the non-human primate Papio ursinus is suitable for the study of bone loss in post-menopausal women.     

Age-related changes of vertebral bone mineral density in Russian population]

Vertebral trabecular bone mineral density (BMD) was measured by quantitative computed tomography (QCT) in 1061 subjects (610 females and 451 males aged from 7 to 91 and from 12 to 89, respectively) with known history of diseases or taking medicines affecting bone metabolism. Peak BMD values in our patients were observed at the age of 20-29 years with further gradual decrement in men and more steep in women. Negative relationship between BMD and age was r = -0.991 for men and r = -0.968 for women. Analyzing BMD changes by decades we observed the largest decrement in men after 60 (13.1% for 60-69 and 14.1% for 70-79 years of age) and in women after 50 (22.5% for 50-59, 22.1% for 60-69 and 20.8% for 70-79 years) which was most probably due to decline in sex hormones production that is known to significantly influence bone metabolism. This was confirmed by BMD values three-phase approximation in women showing the lowest rate of calcium loss by trabecular bone in reproductive period (1.9 mg/cm3/yr) and the highest in perimenopause (3.98 mg/cm3/yr). Annual calcium loss in postmenopause was 2.22 mg/cm3.     

Vertebral pathologies in two early modern period (16th-19th century) populations from Croatia

In order to test to what degree Schmorl's nodes (SN), osteophytosis of the vertebral bodies (VO), and osteoarthritis of the articular facets (OA) are useful indicators of activity-related stress, an analysis of their frequencies and severity of expression was conducted in two early Modern period skeletal samples from Croatia--Koprivno and Sisak. Historic and contemporary ethnographic sources suggest that living conditions were more demanding in Koprivno, and that a sexual division of labor existed in both populations. A total of 2,552 vertebral bodies (990 from Koprivno and 1,562 from Sisak) and 5,186 articular facets (2,135 from Koprivno and 3,051 from Sisak) were analyzed. Koprivno exhibits significantly higher total frequencies of SN, VO, and OA than Sisak, and the total frequencies of SN and OA in both series are significantly higher in males. When, however, the series were analyzed by age and sex categories, the same trend was noted only in SN. The frequencies and severity of VO and OA could not be interpreted in keeping with the historic and contemporary ethnographic sources and were additionally, unlike SN, found to be strongly correlated with increased age. This study, therefore, suggests that while SN are useful indicators of different lifestyles and/or different activity patterns between various archaeological populations, VO and OA are-possibly because of their more varied etiologies-less useful markers of activity-related stress.     

Analysis of the bone metabolism by quantitative computer tomography and clinical chemistry in a primate model (Callithrix jacchus)

Background Common marmosets are widely used as experimental primates; however, little is still known about their bone physiology. Therefore, the aim of our study was to analyse body weight, age and bone‐specific blood parameters in relation to morphological bone parameters. Methods Fifty‐eight common marmosets were analysed for blood calcium (Ca), inorganic phosphor (P_i), alkaline phosphatase (AP) and 17‐β‐estradiol (E2). The examination of bone parameters was undertaken in the lumbar spine by computer tomography. Results There was a correlation between bone mineral density (BMD) and body weight, trabecular area ratio and polar moment as well as between BMD and AP or Ca (only males), whereas there were no correlations between BMD and age, P_i or E2 in all analysed genders. Conclusions Our data support the assumption that the common marmoset is a reliable primate model to study changes in bone metabolism because of the similarity of our results to humans.     

Brief and precarious lives: infant mortality in contrasting sites from medieval and post-medieval England (AD 850-1859)

This study compares the infant mortality profiles of 128 infants from two urban and two rural cemetery sites in medieval England. The aim of this paper is to assess the impact of urbanization and industrialization in terms of endogenous or exogenous causes of death. In order to undertake this analysis, two different methods of estimating gestational age from long bone lengths were used: a traditional regression method and a Bayesian method. The regression method tended to produce more marked peaks at 38 weeks, while the Bayesian method produced a broader range of ages and were more comparable with the expected "natural" mortality profiles.At all the sites, neonatal mortality (28-40 weeks) outweighed post-neonatal mortality (41-48 weeks) with rural Raunds Furnells in Northamptonshire, showing the highest number of neonatal deaths and post-medieval Spitalfields, London, showing a greater proportion of deaths due to exogenous or environmental factors. Of the four sites under study, Wharram Percy in Yorkshire showed the most convincing "natural" infant mortality profile, suggesting the inclusion of all births at the site (i.e., stillbirths and unbaptised infants).     

Genetics and bone. Using the mouse to understand man

The rationale for use of inbred strains of mice in bone research is well recognized and includes: a) practical factors (economics of scale, rapid development of adult status, pre-existing knowledge, down-sized technologies) and b) proven methodologies for genetic studies (polygenic trait analyses, mapping tools, genomic sequencing, methods for gene manipulation). Initial investigations of inbred strains of mice showed that femoral and lumbar vertebral volumetric bone mineral density (BMD, mg/mm(3)) by pQCT varied in excess of 50% for femurs and 9% in vertebral BMD. Two strains - low BMD C57BL/6J (B6) mice and high BMD C3H/HeJ (C3H) - were investigated for insights to their BMD diversity. B6C3F2 females derived from intercrossing B6C3F1s were raised to adult skeletal status at 4 months, then necropsied for phenotyping of bone and genotyping of genomic DNA. 1000 F2 females were genotyped for PCR product polymorphisms on all 19 autosomes at approximately 15 cM. Genome wide analyses for genotype-phenotype correlations showed 10 chromosomes (Chrs) carried genes for femoral and 7 Chrs for vertebral BMD. LOD scores ranged from 2.90 to 24.4, and percent of F2 variance accounted for ranged from 1 to 10%. Analyses of main effects revealed both dominant-recessive and additive inheritance patterns. Both progenitor strains carried alleles with positive and negative effects on BMD of each bone sites. A remarkable array of additonal skeletal phenotypes (femur and vertebral geometry, strength measures, serum markers) also proved polygenic in nature, with complex segregation patterns. Verification of BMD quantitative trait loci (QTLs) was undertaken by creating congenic B6 strains carrying individual QTL regions from C3H. Following 6 cycles of backcrossing a QTL-containing region from C3H to the B6 strain, N6F2 congenic strain mice were aged to 4 months, then genotyped for the QTL region and phenotyped for skeletal traits. Comparison of mice homozygous for C3H alleles versus homozygous for B6 alleles in the QTL regions showed that femoral BMD increased or decreased significantly in congenic strains, as was predicted from F2 data. Gender differences specific to BMD QTLs have been revealed, as have more than 30 additional phenotypes associated with cortical and trabecular structural parameters and biomechanical properties.     

Setup of a bone aging experimental model in the rabbit comparing changes in cortical and trabecular bone: Morphological and morphometric study in the femur

Bone aging was studied in an experimental model (rabbit femur) in three populations aged 0.5, 1.5, and 7.5 years. Cortical bone histology was compared with a data set from a 1.5‐month‐old population of an earlier published paper. From 0.5‐year‐old onward, the mean femur length did not increase further. Thereafter, the mean marrow area increased and the cortical area decreased significantly with aging. This was associated with a structural pattern transformation from plexiform to laminar and then Haversian‐like type. The distal meta‐epiphysis bone trabecular density of the oldest populations also was significantly lower in specific regions of interest (ROI). Percentage sealed primary vascular canals in laminar bone significantly increased with aging without variation of percentage sealed secondary osteons. Remodeling rate reflected by the density of cutting cones did not significantly change among the age populations. These data suggest that laminar bone vascular pattern is more functional in the fast diaphyseal expansion but not much streamlined with the renewal of blood flow during secondary remodeling. Bone aging was characterized by: 1) secondary remodeling subendosteally; 2) increment of sealed primary vascular canals number; 3) increased calcium content of the cortex; 4) cortical and trabecular bone mass loss in specific ROIs. Taken together, the present data may give a morphological and morphometric basis to perform comparative studies on experimental models of osteoporosis in the rabbit. J. Morphol. 276:733–747, 2015. © 2015 Wiley Periodicals, Inc.     

Gender-related changes in three-dimensional microstructure of trabecular bone at the human proximal tibia with aging

Despite increasing interest in age- and gender-related bone alterations, data on trabecular microstructure at the proximal tibia are scarce. The aim of this study was to identify trabecular microstructural change at the human proximal tibia with age and gender, using micro-computed tomography (micro-CT) and scanning electron microscopy (SEM). Fifty-six proximal tibias from 28 Japanese men and women (57-98 years of age) were used in this study. The subjects were chosen to give an even age and gender distribution. Both women and men were divided into three age groups, middle (57-68 years), old (72-82 years) and elderly (87-98 years) groups. The trabecular bone specimens from the medial compartment of the proximal tibial metaphysis were examined. Trabecular bone mineral density (BMD), bone volume fraction (BV/TV) and trabecular thickness (Tb.Th) decreased between the middle-aged and elderly groups similarly in women and men. However, trabecular number (Tb.N) decreased by 13% between the middle-aged and elderly groups in women and nearly double that in men. As compared with women, men had higher BV/TV and lower trabecular separation (Tb.Sp) in the old age and elderly groups, and higher Tb.N and connectivity density (Conn.D) in the elderly group. Increased trabecular resorbing surfaces, perforated or disconnected trabeculae and microcallus formations were observed with age. These findings indicate that both BMD and BV/TV decreased at the proximal tibia with age similarly for women and men, but significant differences between women and men were observed for some microstructural parameters. These findings illustrate potential mechanisms underlying osteoporotic proximal tibial fracture.     

睾酮对去睾丸家兔骨密度及血清钙磷的影响

目的:观察去睾丸和睾酮补充对雄兔骨密度和血清钙、镁、磷的影响.方法:周龄相同的雄性新西兰白兔随机分成对照组、去睾丸组和睾酮补充组(去睾丸后肌注十一酸睾酮).同等条件下饲养20周后测量各组兔全身骨密度、腰椎骨密度、股骨颈骨密度,并检测血清总睾酮(TT)、雌二醇(E2),脱氢表雄酮(DHEA)水平以及血清钙(Ca2 )、游离钙([Ca2 ]i)镁(Mg2 )、磷(P)和碱性磷酸酶(AKP)浓度.结果:去睾丸组血清TT水平明显下降(P<0.01),睾酮补充组血清TT水平升高接近对照组(P>0.05).去睾丸组血清E2和E2/TT比明显高于对照组(P<0.01),睾酮补充组血清E2和E2/TT下降,接近对照组水平(P均>0.05).与对照组相比,去睾丸组血清Ca2 、[Ca2 ]i、Mg2 以及AKP浓度明显升高(P均<0.01),睾酮补充组血清Ca2 、[Ca2 ]i、Mg2 以及AKP浓度较去睾丸组低,接近对照组水平(P>0.05).股骨颈骨密度在去睾丸组明显低于对照组和睾酮补充组(P<0.01),而后两组无差别(P>0.05).结论:去睾丸后雄兔血清TT明显下降,E2和E2/TT比以及Ca2 、[Ca2 ]i、Mg2 和AKP浓度明显升高,骨密度显著下降,睾酮补充使上述异常明显改善.     

Fluoxetine treatment increases trabecular bone formation in mice

Mounting evidence exists for the operation of a functional serotonin (5-HT) system in osteoclasts and osteoblasts, which involves both receptor activation and 5-HT reuptake. In previous work we showed that the serotonin transporter (5-HTT) is expressed in osteoclasts and that its activity is required by for osteoclast differentiation in vitro. The purpose of the current study was to determine the effect of treatment with fluoxetine, a specific serotonin reuptake inhibitor, on bone metabolism in vivo. Systemic administration of fluoxetine to Swiss-Webster mice for 6 weeks resulted in increased trabecular BV and BV/TV in femurs and vertebrae as determined by micro-computed tomography (microCT). This correlated with an increase in trabecular number, connectivity, and decreased trabecular spacing. Fluoxetine treatment also resulted in increased volume in vertebral trabecular bone. However, fluoxetine-treated mice were not protected against bone loss after ovariectomy, suggesting that its anabolic effect requires the presence of estrogen. The effect of blocking the 5-HTT on bone loss following an LPS-mediated inflammatory challenge was also investigated. Subcutaneous injections of LPS over the calvariae of Swiss-Webster mice for 5 days resulted in increased numbers of osteoclasts and net bone loss, whereas new bone formation and a net gain in bone mass was seen when LPS was given together with fluoxetine. We conclude that fluoxetine treatment in vivo leads to increased bone mass under normal physiologic or inflammatory conditions, but does not prevent bone loss associated with estrogen deficiency. These data suggest that commonly used anti-depressive agents may affect bone mass.     

Skeletal manifestations of rickets in infants and young children in a historic population from England

Gross and radiographic changes characteristic of inadequate bone mineralization due to rickets are described in 21 immature skeletons from a 19th century urban population from Birmingham, England. The aims of the study are as follows: to evaluate and if possible augment existing dry-bone criteria for the recognition of rickets in immature skeletal remains; to investigate the value of radiography for the paleopathological diagnosis of rickets; and to compare and contrast the expression of rickets in this group with that previously documented for a rural agrarian population from Wharram Percy, England. Some gross skeletal signs of rickets which were not previously well-documented in paleopathological studies are noted. The worth of radiography for evaluating structural changes to both cortical and trabecular bone in the disease is demonstrated, and features useful for the interpretation of vitamin D deficiency are discussed. The pattern of skeletal elements affected and the severity of changes differs in the Birmingham group from that seen in the comparative rural population. It is emphasized that a variety of factors may influence the expression of rickets in paleopathological material, including rate of skeletal growth, age cohort affected, and intensity of vitamin D deficiency. Nevertheless, careful analysis, not only of the frequency of rickets but also of the degree of severity of lesions and the patterning with respect to skeletal elements affected, may enable more nuanced understanding of the biocultural context of the disease in earlier populations.     

骨质疏松兔松质骨微观结构和微观成分的时间序贯性变化

目的:研究去势手术建立骨质疏松兔模型中松质骨微观结构和微观成分的时间序贯性变化。方法:40只新西兰白兔随机分为假手术组(sham组,n=20)和骨质疏松组(OP组,n=20)。OP组兔子给予去势手术处理,sham组给予假手术处理。分别于术后的0周、4周、6周、8周,利用DXA测量腰椎骨密度(每组每个时间点选择5只动物)。之后处死动物,采集腰椎标本。利用Micro-CT、FTIR、腰椎轴向压缩试验得到松质骨的微观结构、微观成分(骨矿盐晶体和胶原)和宏观力学参数。利用t检验比较同一时间点两组之间的相关参数。结果:OP组BMD逐渐下降,松质骨微观结构逐渐疏松,微观组成属性逐渐改变,宏观力学强度均逐渐下降。FTIR在4周时即检测到OP组腰椎骨矿盐和胶原基质比(P=0.046)、骨矿盐结晶度(P=0.018)、胶原交联比(P=0.006)发生显著性改变,早于BMD和微观结构的变化。OP组腰椎宏观生物力学强度在第8周时达到最低点(P=0.001)。结论:去势手术后,腰椎松质骨骨矿盐晶体和胶原属性最早发生变化,松质骨微观成分和微观结构的改变是导致椎体强度明显改变的原因。FTIR技术可以较早的检测到骨质疏松发生过程中骨组织微观成分的改变。