顶骨凹陷变薄的形态学研究

本文从1480个颅骨中发现顶骨凹陷变薄的有16例。对其性别、年龄、颅形以及凹陷的形状、深度和骨质厚度作了观测,利用骨磨片和X线摄片对凹陷部分骨质进行了研究。结果表明此种凹陷均见于老年人,多数为双侧性。凹陷是由外板内凹而成,不涉及周围组织。X线侧位片显示凹陷处有宽带状低密度阴影。骨组织磨片显示在骨改建过程中,出现未满围骨单位增多,骨陷窝闭塞,造成局部的骨萎缩。     

Reversible inhibition of osteoclastic activity by bone-bound gallium (III).

Gallium(III) is a new therapeutic agent for hypercalcemia. Ga3+ reduces osteoclast action, but how it inhibits the cell's physiology is unknown. In vivo, 7-12 microM Ga(III) reduces calcium release from bone, but surprisingly, 10-100 microM Ga3+ added to isolated avian osteoclasts did not reduce their degradation of L-(5-3H)-proline bone. 3H-proline labels bone collagen specifically, and collagenolysis is an excellent indicator of bone dissolution because collagen is the least soluble component of bone. Ga(III) greater than 100 microM inhibited osteoclasts in vitro, but also killed the cells. To resolve this apparent conflict, we measured 67Ga distribution between bone, cells, and media. Gallium binds avidly but slowly to bone fragments. One hundred micrograms of bone clears 60% of 1 microM gallium from 500 microliters of tissue culture medium, with steady state at greater than 24 h. Osteoclasts on bone inhibited gallium binding capacity approximately 40%, indicating a difference in available binding area and suggesting that osteoclasts protect their substrate from Ga binding. Less gallium binds to bone in serum-containing medium than in phosphate-buffered saline; 30% reduction of the affinity constant suggests that the serum containing medium competes with bone binding. Consequently, the effect of [Ga] on bone degradation was studied using accurately controlled amounts of Ga(III) pre-bound to the bone. Under these conditions, gallium sensitivity of osteoclasts is striking. At 2 days, 100 micrograms of bone pre-incubated with 1 ml of 1 microM Ga3+, with 10 pmoles Ga3+/micrograms bone, was degraded at 50% the rate of control bone; over 50 pM Ga3+/micrograms bone, resorption was essentially zero. In contrast, pre-treatment of bone with [Ga3+] as high as 15 microM had no significant effect on bone resorption rate beyond 3 days, indicating that gallium below approximately 150 pg/micrograms bone acts for a limited time and does not permanently damage the cells. We conclude that bone-bound Ga(III) from medium concentrations less than 15 microM inhibits osteoclasts reversibly, while irreversible toxicity occurs at solution [Ga3+] greater than 50 microM.     

Human temporal bone from the lower Paleolithic site of Castel di Guido, near Rome, Italy

The Castel di Guido site, with an estimated age of approximately 300,000 years, has yielded abundant animal remains, Acheulian stone and bone bifaces, and small tools. On the surface of the original deposit, turned over by agricultural activities, fragments of human remains were discovered between 1980 and 1986, including a temporal bone described here.     

Age effects on intracortical microstructure and cortical thickness in adult saddle-back tamarins

Intracortical bone remodeling and cortical thickness data were collected from middiaphyseal thin sections of the humerus, ulna and tibia for 47 specimens ofSaguinus fuscicollis. Individuals were classified into age cohorts: Young Adult, Mid-adult I, Mid-adult II and Old Adult. Correlation analyses revealed significant relationships between age cohort and the number of osteons for the humerus and ulna, and between age cohort and non-Haversian canals for each of the three long bone elements. Significant relationships between age cohort and dimension of cortex size suggested an age-related pattern of cortical shifting in the ulna and older-age bone loss in the tibia.     

辽宁海城小孤山遗址发掘简报

从小孤山晚更新世洞穴遗址出土了38种哺乳动物化石、上万件石制品以及一批制作精美的骨角制品和装饰品。石器工业在技术与类型上和华北旧石器关系密切。大致相同的骨针和穿孔兽牙于三十年代曾在周口店山顶洞遗址发现过,但是与欧洲马格德林鱼叉相似的角制鱼叉在中国旧石器文化中是头一次发现。     

Ultrastructural evidence for an osmoregulatory effect of nikkomycin in the mite Tetranychus urticae

Histological effects of the microbial metabolite and chitin synthesis inhibitor complex Nikkomycin (AMS 0896 Bayer Leverkusen) on osmoregulatory organs of all developmental stages of Tetranychus urticae are described. The metabolite, in a concentration of 100 ppm, was applied via the nutritive plant. Mites fed for 2 to 14 days, and then were collected and immediately fixed. Two osmoregulatory organs occur in T. urticae. The Malpighian complex, differentiated only in females, shows an increased number of apical microvilli in the epithelium of the distal regions after metabolite application, thus resulting in an enlargement of the surface area. Changes in the second osmoregulatory organ, the coxal organ, after Nikkomycin application include depositions of membranous bodies in the lumen as well as in cytoplasmic vacuoles of the proximal tubule. Additionally, an increase in the luminal diameter occurs. Numerous vacuoles of different contents are observed in the cytoplasm of the distal tubule. Consequences of histological alterations in osmoregulatory organs after Nikkomycin application are discussed with special reference to the composition of salivary secretions.     

Actions of calcitonin, parathyroid hormone, and prostaglandin E2 on cyclic AMP formation in chicken and rat osteoclasts

The effects of calcitonin, parathyroid hormone, and prostaglandin E2 on cyclic AMP production were studied in osteoclast-rich cultures derived from medullary bone of laying hens and from the long bones of newborn rats. Cyclic AMP was assayed biochemically in replicate cultures, and furthermore, changes in cytoplasmic fluorescence were sought by indirect immunofluorescence with rabbit anti-cyclic AMP and FITC-labelled goat anti-rabbit IgG. Treatment of rat osteoclasts with calcitonin increased cyclic AMP formation as measured biochemically, and this was confirmed by the immunofluorescence method. No such increase took place in chick osteoclasts. Prostaglandin E2 increased cyclic AMP production in both rat and chick osteoclasts as determined by both methods. Since the immunofluorescence method failed to detect a response to parathyroid hormone either in chick or rat osteoclasts, its variable biochemical effects were concluded to be due to actions on contaminating osteoblasts in the cultures. Thus it has been possible with a combined biochemical and immunocytochemical approach to define the cyclic AMP responses to the calcium-regulating hormones in rat and chick osteoclasts. The failure of calcitonin to increase cyclic AMP in chick osteoclasts identifies a need to investigate the nature of calcitonin action on avian osteoclasts, which may contribute to understanding of its actions on mammalian cells.     

A high affinity,calmodulin-responsive (Ca2+ + Mg2+)-ATPase in isolated bone cells

Although acute alterations in Ca²⁺ fluxes may mediate the skeletal responses to certain humoral agents, the processes subserving those fluxes are not well understood. We have sought evidence for Ca²⁺-dependent ATPase activity in isolated osteoblast-like cells maintained in primary culture. Two Ca²⁺-dependent ATPase components were found in a plasma membrane fraction: a high affinity component (half-saturation constant for Ca²⁺ of 280 nM, $\text{V}{}_{\mathrm{<mtext>max</mtext>}}$ of 13.5 nmol/mg per min) and a low affinity component, which was in reality a divalent cation ATPase, since Mg²⁺ could replace Ca²⁺ without loss of activity. The high affinity component exhibited a pH optimum of 7.2 and required Mg²⁺ for full activity. It was unaffected by potassium or sodium chloride, ouabain or sodium azide, but was inhibited by lanthanum and by the calmodulin antagonist trifluoperazine. This component was prevalent in a subcellular fraction which was also enriched in 5′-nucleotidase and adenylate cyclase activities, suggesting the plasma membrane as its principal location. Osteosarcoma cells, known to resemble osteoblasts in their biological characteristics and responses to bone-seeking hormones, contained similar ATPase activities. Inclusion of purified calmodulin in the assay system caused small non-reproducible increases in the Ca²⁺-dependent ATPase activity of EGTA-washed membranes. Marked, consistent calmodulin stimulation was demonstrated in membranes exposed previously to trifluoperazine and then washed in trifluoperazine-free buffer. These results indicate the presence of a high affinity, calmodulin-sensitive Ca²⁺-dependent ATPase in osteoblast-like bone cells. As one determinant of Ca²⁺ fluxes in bone cells, this enzyme may participate in the hormonal regulation of bone cell function.     

Matrix Gla protein, a new gamma-carboxyglutamic acid-containing protein which is associated with the organic matrix of bone

A new protein has been isolated from CaCl2/urea extracts of demineralized bovine bone matrix. This protein has five to six residues of the vitamin K-dependent amino acid, gamma-carboxyglutamic acid (Gla), and we have accordingly designated it matrix Gla protein. Matrix Gla protein is a 15,000 dalton protein whose amino acid composition includes a single disulfide bond. The absence of 4-hydroxyproline in matrix Gla protein demonstrates that it is not a precursor to bone Gla protein, 5,800 dalton protein which has a residue of 4-hydroxyproline at position 9 in its sequence. Matrix Gla protein also does not cross-react with antibodies raised against bone Gla protein.     

Cortical bone growth and dietary stress among subadults from Nubia's Batn el Hajar

Cortical bone growth is analyzed for 174 children from a Medieval Christian population at Kulubnarti in the Batn el Hajar of Sudanese Nubia (550–1450 AD ). Using the tibia as a representative long bone, total subperiosteal area, cortical area, medullary area, and percent cortical area at midshaft were calculated. While growth in total and cortical areas, as well as in length, appear to be fairly well maintained, percent cortical area reveals unusual growth patterns which reflect excessive endosteal resorption. Compared to the relative reduction in bone mass which has been observed in malnourished living children, as well as with previously reported evidence for stress in the Kulubnarti population, the present data support an interpretation of nutritionally related stress and of no major diachronic dietary change.