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Bone is remodelled constantly through a balance of bone formation and resorption. This process can be affected by various factors such as hormones, vitamins, nutrients and environmental factors, which can create an imbalance resulting in systemic or local bone alteration. The aim of the present study was to analyse the changes in bone mineral density (BMD) over time in skulls of ringed seals (Pusa hispida) from the Baltic and Greenland using museum samples. Overall, 303 skulls (102 Male, 89 Female, 112 unknown) were used for bone investigations and were divided into three periods according to collection year: before 1958 (n = 167), between 1958 and 1989 (n = 40) and after 1994 up to 2019 (n = 96). All skulls were examined by dual-energy X-ray absorptiometry to obtain the BMD. Skull BMD of the Baltic seals was positively correlated with the historical polychlorinated biphenyls (PCB) contamination having potential effects on the constitution of bones. BMD fluctuated between the three study periods (LM: p-value < 0.001, F-value = 47.5) with the lowest BMD found between 1897 and 1957, in the Gulf of Bothnia, where the highest peak of contaminant concentration was in the second period. BMD levels increased with increasing PCB concentration (LM: p < 0.001). The Greenland population showed significant lower BMD levels in the pollution and post-pollution period than the Baltic population (LM: p < 0.001). It also revealed a higher BMD in males than in females (LM: p = 0.03). In conclusion, the variations between 1829 and 2019 in the Baltic Sea and Greenland may to a certain extent reflect normal fluctuations; however, this study revealed several factors affecting BMD, including sex and PCB levels.

The post-depositional alteration of cave sediments is of critical importance for the recognition, identification and investigation of geoarchaeological and palaeoenvironmental evidence. There have been relatively few studies of tropical cave sediments using micromorphology and this work represents one of the most detailed with 26 samples taken from deposits in the West Mouth of the Great Cave of Niah that cover the last >∼55,000 BP, and contain the earliest known evidence for the remains of modern humans in Southeast Asia. Cave sediments situated in the humid tropics are subject to relatively high temperatures and moisture conditions that promote high rates of chemical alteration and geomorphic change. This paper outlines those post-depositional features that occurred in situ in the West Mouth and include: translocation and concentration; bioturbation; excrement; bone alteration; plant alteration; clast alteration and guano decomposition. It examines their implications for recognising past human activities (e.g. fire-altered materials), the preservation of archaeological remains, the nature of palaeoenvironments and of localised physical and bio-geochemical processes.

Inflammatory bowel diseases (IBDs) are characterized by a multifactorial partially unknown etiology that involves genetic, immunological and environmental factors. Up to 50% of IBD patients experience at least one extraintestinal manifestation; among them is the involvement of bone density which is referred to as metabolic bone disease (MBD), including osteopenia and osteoporosis. Bone alterations in IBDs population appear to have a multifactorial etiology: Decreased physical activity, inflammation-related bone resorption, multiple intestinal resections, dietary malabsorption of minerals and vitamin D deficiency, genetic factors, gut-bone immune signaling interaction, steroid treatment, microbiota and pathogenic micro-organisms interaction, and dietary malabsorption of minerals, that, all together or individually, may contribute to the alteration of bone mineral density. This review aims to summarize the prevalence and pathophysiology of metabolic bone alterations in IBD subjects outlining the main risk factors of bone fragility. We also want to underline the role of the screening and prophylaxis of bone alterations in Crohn's disease and ulcerative colitis patients and the importance of treating appropriately MBD.

Resumo A osteonecrose dos maxilares é uma alteração óssea que pode ser induzida pelo uso de drogas indicadas para o tratamento de pacientes com osteoporose e tumores malignos. Inicialmente acreditava-se estar associada apenas ao uso de bisfosfonatos, atualmente sabe-se que também está vinculada ao uso de outro antirresorptivo (denosumabe) e de antiangiogênico (bevacizumabe). Não se sabe ao certo qual é o mecanismo de desenvolvimento e ainda não existe um protocolo único de tratamento definido, mas existem diversos trabalhos sendo publicados sobre o tema. Com a crescente quantidade de casos relatados é de suma importância que o profissional de saúde saiba diagnosticar, identificar os riscos e tratar essa condição. Abstract Osteonecrosis of the jaws is a bone alteration that can be induced using drugs indicated for the treatment of patients with osteoporosis and malignant tumors. Initially it was believed to be associated only with the use of bisphosphonates, currently it is known that it is also linked to the use of other antiresorptive (denosumab) and antiangiogenic (bevacizumab). It is not known what the development mechanism is and there is still no single defined treatment protocol, but there are several papers being published on the topic. With the increasing number of cases reported, it is extremely important that the health professional can diagnose, identify the risks and treat this condition. Resumen La osteonecrosis de los maxilares es una alteración ósea que puede ser inducida por el uso de drogas indicadas para el tratamiento de pacientes con osteoporosis y tumores malignos. Inicialmente se creía estar asociada sólo al uso de bisfosfonatos, actualmente se sabe que también está vinculada al uso de otro antirresorptivo (denosumab) y de antiangiogénico (bevacizumabe). No se sabe con certeza cuál es el mecanismo de desarrollo y aún no existe un protocolo único de tratamiento definido, pero existen diversos trabajos siendo publicados sobre el tema. Con la creciente cantidad de casos reportados es de suma importancia que el profesional de salud pueda diagnosticar, identificar los riesgos y tratar esa condición.

This paper focuses on the study of bone alterations in fumier deposits from an experimental point of view. Fumiers are characteristic of livestock enclosures in the Mediterranean area used from the Neolithic to the Bronze Age. They originate from the process of burning livestock dung piles to reduce the volume of dung accumulation and to rid these spaces of parasites. Therefore, diverse taphonomic processes take part in the formation of these types of deposits, making it difficult to interpret them, despite numerous multidisciplinary studies. This work specifically focuses on bone burning alterations. Two experiments were set up consisting of bone burning in dung piles. Sheep and goat dung was used with different matrix, texture and humidity features. The sample was made up of defleshed fresh, boiled and dry bone fragments from small and medium-sized species. As seen in previous experiments, the burning time and temperature in the two experiments varied due to these different dung features. The resulting bone sample was analyzed using taphonomic methods. Bone alterations essentially depend on the time and intensity of the dung burning. Bone condition is a secondary determining factor. The color degrees were high and coherent with the degree of dung alteration. Cortical damage was more abundant in fresh and boiled bones than in dry bones. No meaningful differences were identified with regard to bones burned in hearth combustions.

We describe osteichthyan remains from the Upper Jurassic of the Ameghino (= Nordenskjöld) Formation of the Antarctic Peninsula. The fossils are referred to a suspension-feeding pachycormid based on the shape, morphology, and presence of acus fanunculi (needle teeth) on their gill rakers. Due to the fragmentary condition of the Antarctic material, we refer it to aff. Asthenocormus. The remains described here represent the first record of a suspension-feeding pachycormid from the Upper Jurassic of the Antarctic Peninsula and the oldest pachycormid yet recovered from Antarctica. The new fossil fish supports a possible early dispersal route through the Mozambique Corridor (= Trans-Gondwana or South African Seaway). We also describe the weathering produced by modern lichens, which might be misinterpreted as original bone structure. Fil: Gouiric Cavalli, Soledad. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Rasia, Luciano Luis. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Marquez, Gonzalo Javier. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Cátedra de Palinología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Rosato, Vilma Gabriela. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Laboratorio de Entrenamiento Multidisciplinario para la Investigación Tecnológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Scasso, Roberto Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; Argentina Fil: Reguero, Marcelo Alfredo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina

Objectives The aim of this work is to describe the taphonomic signatures of the Aroeira 3 cranium, with a specific focus on cranial breakage, comparing the cranium with other Middle and Upper Pleistocene hominin fossils in order to approximate the cause of death and the biological agencies and geologic processes involved in the taphonomic record of this specimen. Aroeira‐3 was recovered from Acheulean layer X of Gruta da Aroeira (Portugal), dated to 390–436 ka. Materials and methods Taphonomic analyses noted surface modifications employing standard methods. The cranial breakage pattern of Aroeira 3 was analyzed to assess the presence/absence of perimortem (fresh bone) and postmortem (dry bone) fractures and the possible causes of perimortem skull bone fractures. Results Aroeira 3 presents substantial bone loss of the left supraorbital arch and the outer cranial table of the frontal squama. Most of the fractures present features consistent with postmortem injuries. The fracture to the posterior region of the parietal bone, however, displays features more usually present in perimortem bone fractures. No evidence of anthropogenic activity or of carnivore modification has been identified. None of the expected features of interpersonal conflict are observed. Finally, the bone loss in the frontal squama and the supraorbital arch could be attributed to different agencies, and a traumatic event cannot be totally ruled out as origin of the bone alteration. Discussion Cannibalism, secondary treatment of the corpse and accumulation induced by carnivores can all be discarded, making an accident the most plausible explanation for the cranial fracture.

Histological analysis is widely applied to archaeological and fossil bones in order to identify diagenetic changes in bone microstructure. Diagenetic processes, affecting bones from the body deposition to the discovery, strongly depend on environmental conditions; therefore the study of diagenetic alterations provides valuable information on the taphonomic history of bones and on their burial environment. Histological analysis was performed on 58 samples of human compact bone found at Al Khiday (Khartoum, Sudan), a multi-stratified archaeological site that revealed a cemetery with distinct burial phases dating from the Early Holocene to the II century AD. The well-defined archaeological context provides a set of bone samples belonging to the same site but buried in different phases and under different environmental conditions: Central Sudan was characterised by a humid environment with seasonal swamps and palaeo-lakes in the Early Holocene, while in the II century AD the environmental conditions were more similar to the current arid climate of the Sub-Saharan belt. Scanning electron microscopy (SEM) and high-resolution X-ray computed micro-tomography (μ-CT) analysis revealed extensive bacterial and fungal attack, and secondary phases precipitation and dissolution in the samples. The analysis of textural relationships between each diagenetic feature enabled to establish a relative chronological sequence of events acting during burial. Moreover, different patterns of diagenetic alterations were observed for burial phases of different ages, proving a strong relationship between diagenesis and environmental conditions.

This work presents data obtained from experiments conducted on wild and captive wolves. Actualism is a very useful tool for taphonomic studies, as it allows us to understand the behavior of fauna in the past. However, not many past experimental studies have dealt with wolves as taphonomic agents. The results of the study show that wolves modify animal carcasses in advanced stages that include fracturing the bones in order to consume the marrow. By comparing captive and wild wolves, we observe that captive wolves often modify ungulate carcasses to a greater degree than do wild wolves. Moreover, factors such as the size of the ungulate and the period of availability of the carcass influence the type and degree of bone alteration. Tooth mark dimensions also allow us to compare wolves with other large carnivores and reveal that wolves differ significantly from large felids and ursids, and they have more in common with hyenids.

Objective To assess the degenerative bone changes of the jaw head and the condylar mobility regarding gender and age. Methods The sample was composed of 106 CBCT images for TMJ region from patients over 18 years old, from both genders, from the archives of a radiological clinic in the city of Campina Grande, Paraíba, Brazil. The images were obtained from patients in maximum intercuspal and maximum mouth opening. The images were examined by a radiologist, through the software Xoran CAT(r), using a monitor with high resolution of and maximum color quality (12 bits) in a low light environment. It was assessed tomographic aspects of bone degenerative changes (flattening, erosion, osteophytes, bone sclerosis and pseudocyst) of both TMJ of each patient. The association among the degenerative changes of the jaw head, gender and age were investigated through Fisher's exact test, G-test and chi-squared test. The data obtained regarding condylar mobility (normo, hyper and hypoexcursion), location (right unilateral, left unilateral and bilateral) were also submitted to descriptive analysis in terms of absolute and relative frequency. Results The most frequent bone alteration was flattening (58.5%), followed by osteophytes (44.3%), erosion (22.6%), sclerosis (13.2%) and pseudocyst (10.4%). Regarding condylar mobility it was observed that normoexcursion (71.7%) was more prevalent. Conclusion The degenerative bone changes occurred more frequently among women and in bilateral location and there was an increasing of alterations according the age. It was not found correlation among condylar mobility and the presence of degenerative bone alterations of the TMJ. RESUMO Objetivo Avaliar as alterações ósseas degenerativas na cabeça da mandíbula e a mobilidade condilar com relação ao gênero e à faixa etária. Métodos A amostra foi constituída por 106 exames de TCFC para a região de ATM de pacientes com mais de 18 anos, do arquivo de uma clínica de radiologia odontológica, localizada na cidade de Campina Grande, PB, Brasil. As imagens foram obtidas com os pacientes em máxima intercuspidação e abertura de boca. As imagens foram examinadas por um radiologista, por meio do próprio software do tomógrafo Xoran CAT(r), usando-se um monitor com alta resolução e máxima qualidade de cor (12 bits) em ambiente com luz reduzida. Foram avaliados os aspectos tomográficos das alterações ósseas degenerativas (facetamento, erosão, osteófitos, esclerose óssea e pseudocisto) de ambas as ATM. As associações entre as alterações degenerativas e o sexo e a faixa etária foram investigadas por meio dos testes exato de Fisher, G e Qui-quadrado. Os dados obtidos quanto à excursão condilar (normoexcursão, hipoexcursão e hiperexcursão), segundo a localização também foram submetidos a análises descritivas. Resultados As alterações mais frequentes foram o facetamento (58,5%), seguido de osteófito (44,3%), erosão (22,6%), esclerose (13,2%) e pseudocisto (10,4%). Em relação à excursão condilar, observou-se que a normoexcursão foi a mais prevalente (71,7%). Conclusão As alterações ósseas degenerativas ocorreram de forma mais frequente em mulheres e de forma bilateral, e houve um aumento da frequência com a idade. Não foi encontrada correlação entre a excursão condilar e a presença de alterações na ATM, sendo a normoexcursão mais frequente.

In bioarchaeology, skeletal biology and paleopathology, periosteal reaction has been variably considered as a non-specific sign of trauma and alternatively as having potentially diagnostic implications. Examination of sixth millennium before present Texas cemeteries falsifies the non-specific trauma hypothesis, while examination of a second millennium before present site reveals a new (at least to Texas) population phenomenon. In contrast to isolated bumps and osteomyelitis, the study of periosteal reaction in early Texas is the study of “virgins,” individuals spared the phenomenon that cause such bone alteration. It is only in the second millennium before present that periosteal reaction becomes widespread, both in population penetrance and in extent of skeleton affected. That pattern has previously been documented for the treponematosis yaws, similar to what has been found in other areas of Archaic North America.

It has been ascertained that metal implantation in the femoral bone of rats with simultaneously induction of immunological reaction leads in all probability to intense bone damage. It is possible that the sum of all qualitative and quantitative haemodynamic and biochemical consequences from the bone injury (implantation) and the immunological reaction are responsible for this result. To investigate the above possibility, we carried out this study with a monthly delay of antigen administration after metal implantation. We found that: a) Bone alterations occur in approximately 50% of experimental animals which received antigen. b) These bone changes are shown radiologically as osteolysis of immunological reaction, respectically. c) These changes are of less intensity than those produced in simultaneous implantation and antigen administration, but of practical importance. d) None of the control animals (without antigen administration) showed any radiologically visible bone alteration. We discuss the clinical usefulness of these results.

This study examines the inhumed individuals of ten Imperial Age Roman graveyards (Fig. 2.1), from several different areas of the Suburb, and concentrates on subjects affected by pathological phenomena of great scientific interest. In particular

Despite the growing interest in deciphering the causes and consequences of obesity-related disorders, the mechanisms linking fat intake to bone behaviour remain unclear. Since bone fractures are widely associated with increased morbidity and mortality, most notably in elderly and obese people, bone health has become a major social and economic issue. Consistently, public health system guidelines have encouraged low-fat diets in order to reduce associated complications. However, from a bone point of view, mechanisms linking fat intake to bone alteration remain quite controversial. Thus, after more than a decade of dedicated studies, this timely review offers a comprehensive overview of the relationships between bone and fatty acids. Using clinical evidences as a starting-point to more complex molecular elucidation, this work highlights the complexity of the system and reveals that bone alteration that cannot be solved simply by taking omega-3 pills. Fatty acid effects on bone metabolism can be both direct and indirect and require integrated investigations. Furthermore, even at the level of a single cell, one fatty acid is able to trigger several different independent pathways (receptors, metabolites...) which may all have a say in the final cellular metabolic response.

We study several algorithms to simulate bone mass loss in two-dimensional and three-dimensional computed tomography bone images. The aim is to extrapolate and predict the bone loss, to provide test objects for newly developed structural measures, and to understand the physical mechanisms behind the bone alteration. Our bone model approach differs from those already reported in the literature by two features. First, we work with original bone images, obtained by computed tomography (CT); second, we use structural measures of complexity to evaluate bone resorption and to compare it with the data provided by CT. This gives us the possibility to test algorithms of bone resorption by comparing their results with experimentally found dependencies of structural measures of complexity, as well as to show efficiency of the complexity measures in the analysis of bone models. For two-dimensional images we suggest two algorithms, a threshold algorithm and a virtual slicing algorithm. The threshold algorithm simulates bone resorption on a boundary between bone and marrow, representing an activity of osteoclasts. The virtual slicing algorithm uses a distribution of the bone material between several virtually created slices to achieve statistically correct results, when the bone-marrow transition is not clearly defined. These algorithms have been tested for original CT 10 mm thick vertebral slices and for simulated 10 mm thick slices constructed from ten 1 mm thick slices. For three-dimensional data, we suggest a variation of the threshold algorithm and apply it to bone images. The results of modeling have been compared with CT images using structural measures of complexity in two- and three-dimensions. This comparison has confirmed credibility of a virtual slicing modeling algorithm for two-dimensional data and a threshold algorithm for three-dimensional data.

Runnymede has large samples of Neolithic and Late Bronze Age animal bones, with contrasting preservation conditions in both periods. The bone evidence has been used to interpret the formation of the site deposits. There are few articulated bones, and no joins were found in butchered bone, indicating that the area studied did not contain primary refuse. Various aspects of bone alteration have been analysed: (i) the proportion of bones with very good surface preservation was high in the in situ Neolithic excavation units and the basal Bronze Age midden, but bones in the upper units were mostly eroded. These units are reworked flood deposits. The greater degree of fragmentation of the bone in the reworked units has been quantified, using a system of recording the ‘zones’ present on each bone, which allows calculation of the fraction present. It is also demonstrated that the reworked units contain a lower proportion of identified bones and a higher proportion of teeth and iaws than the units with well-preserved bone, (ii) Quantification of canid gnawing shows, unexpectedly, that more was recorded on well-preserved bone. Thus recognition of gnawing depends on bone condition. This also confirms that most of the erosion of the bone surface is a post-depositional phenomenon. The sequence of activities is therefore interpreted as follows: meat was cooked and consumed, and the bones discarded for the dogs. At a later stage, larger bones were picked up and thrown away in the river or midden. Some ethnographic examples of periodic cleaning of farming settlements are cited.

Background Rheumatoid arthritis (RA) is associated with periarticular bone loss. In the last decade Digital X-ray Radiogrammetry (DXR) was introduced to quantify periarticular bone loss. Objectives This Meta-analysis evaluates potential factors which influence periarticular bone loss as measured by DXR in patients with RA. Methods A systemic literature evaluation was performed to include studies that used DXR to measure cortical periarticular bone loss at the metacarpal bones (DXR-BMD) in RA-patients. Three independent researchers assessed the quality of the studies. DXR-BMD was compared to age, gender, disease duration, C-reactive Protein (CRP), the occurrence of rheuma factor and HAQ-DI (Health Assessment Questionnaire). Results 19 relevant studies, which fulfilled the inclusion criteria, included a quantity of 2673 RA-patients. Gender and age significantly influence DXR-BMD. A prolonged disease duration of RA was associated with a lower DXR-BMD. The Meta-analysis showed a reduced DXR-BMD (-3.3 %) in patients with elevated CRP-levels. Additionally, rheuma factor positive patients present a progressive loss of DXR-BMD. Conclusions This Meta-analysis revealed an impact of age and gender on DXR-BMD. In this way age and gender independent parameters of bone mineral density (e. g. T-Score) should be used. Additionally, the Meta-analysis clearly verified an obvious impact of high disease activity with a pronounced inflammatory activity on periarticular mineralisation resulting in a cortical metacarpal bone loss. Consequently, DXR seems to be a diagnostic tool to evaluate bone alteration related to disease activity in RA and functions as surrogate maker for radiological progression, may be optimizing the individual therapeutic strategies. Disclosure of Interest A. Pfeil Grant/research support from: Research Grant from Chugai Pharma Ltd, J. Bottcher: None Declared, P. Oelzner: None Declared, G. Wolf: None Declared

Rabbits with hereditary buphthalmus, AXBU/J strain, were fed various levels of supplementary vitamin A or its precursor beta carotene, in addition to a vitamin A deficient diet, to test the hypothesis that the bu gene acts by reducing either the conversion of beta carotene to vitamin A or the utilization of vitamin A. Measurements were taken on an age series of skulls of manifest and of prodromal buphthalmics to see if there were any observable differences in optic foramen size associated with the clinical manifestations of buphthalmus. Constriction of the optic nerve by bone alteration has been reported to be associated with vitamin A deficiency. The original hypothesis was not a tenable one as the rabbit with hereditary buphthalmus readily converted beta carotene to vitamin A, no bony changes in the optic foramen were observed with manifest buphthalmus, high levels of beta carotene or vitamin A were unable to block the clinical development of buphthalmia, and no correlation was observed between intraocular pressure and serum vitamin A levels in rabbits fed either beta carotene or pure vitamin A.

The roentgenograms and clinical records of 630 Mayo Clinic patients with abnormal TMJ roentgenograms seen over a period of 9 years were reviewed. Abnormal TMJ roentgenograms were three times more frequent in women than in men. The highest incidence of TMJ abnormalities, in both men and women, was between the ages of 40 and 70 years. The complaint of pain did not necessarily correlate with roentgenographic evidence of bone changes. The condylar articular surface was the first bony surface of the TMJ to show roentgenographic evidence of destructive disease. Of the 222 patients who had bony crepitus, 164 had roentgenographic evidence of bone change. A decreased range of condylar motion was the most frequently reported abnormality in patients whose TMJ roentgenograms showed no evidence of bone alteration. Neoplasms, sialadenitis, scleroderma, and trigeminal neuralgia were responsible for the TMJ abnormality in forty-four of the 630 cases.

In zwei Reihenuntersuchungen (Sellabereich und Clivusbereich — Medianschnitte) wird die Aktivitat des Knochenumbaues an der Schadelbasis beim erwachsenen Menschen vorwiegend in hoherem Alter histologisch gepruft. Aktiver Umbau gilt nur da als nachgewiesen, wo Osteoclasten und (oder) Osteoplasten angetroffen werden. Knochenan- und -abbau sind auch an der Schadelbasis nicht selten zu beobachten. Auch die Schadelbasis ist an der zeitlebens sich vollziehenden Knochensubstanzerneuerung im allgemeinen mehr oder minder lebhaft beteiligt. Gehemmt erscheint die Umbauaktivitat bei malignen Neubildungen (Kachexie), angeregt bei chronischer Stauungscyanose (Osteopathie pneumique) und unter den besonderen hormonalen Bedingungen der Graviditat. — Es treten wesentliche regionale Unterschiede der Umbauaktivitat hervor, ein Gefalle, dessen Zentrum in der Sella gelegen ist. Die Sella stellt sich dar als Region geringster Knochenstabilitat im Medianbereich der Schadelbasis. Dieses Ergebnis, das mit Rontgenbefunden bei intrakraniellen Druckschwankungen ubereinstimmt, wird graphisch veranschaulicht.

This paper reports on the modification by carnivores of recent equid skeletal remains in the Ross River area, Yukon Territory. The objective of this study is to characterize carnivore modification of skeletal assemblages in terms of bone alteration, carnivore preference for certain bone elements or portions, and patterns of survivorship of elements at recent kill/scavenging sites. The most common types of carnivore alteration observed were tooth furrows, punctures, and curvilinear fracture on smaller elements. Chipping and polish occurred infrequently. Survival of skeletal elements depends on the degree of carcass utilization. Cranial and axial elements were present at all sites; scapulae, innominates, and limbs were absent or dispersed at well-utilized sites. Key words: taphonomy, skeletal modification, archaeological interpretation, faunal analysis, wolves, horse kills, southern Yukon

The therapeutic usefulness of retinoids in dermatology (9,10) and certain cancer diseases (2, 13, 14) has been established recently. One of these compounds attracting major attention is the aromatic retinoid Ro 10-9359 (etretinate). This report reviews the results of the routine preclinical studies performed with this compound.

The radioisotope F18 has a particular affinity for bone tissue and a rapid soft tissue clearance, 1 h after i.v. injection of F18 the radiopharmacon is located almost exclusively in the bone. Osseous regions with increased metabolism show an elevated uptake of the diagnostic agent. This bone seeker was used along with the standard diagnostic procedures in the otitis media chronica epitympanalis. In p.a. directed skull scintigram areas showing “active bone alteration” were able to be differentiated from less active forms of this ear affection F18-scintigraphy therefore offers an additional diagnostic possibility in the evaluation of otitis media chronica epitympanalis.