Search results for "CALCIFICATION"

Some effects of salmon calcitonin on calcium metabolism in the crustaceanOrchestia during the molt cycle

1989

In the terrestrial amphipod Orchestia cavimana, investigations of the variations of the total hemolymphatic calcium during the normal molt cycle revealed that a calcium balance is maintained in intermolt, as observed in numerous crustaceans. During premolt, hypercalcemia occurs, related to the marked calcium reabsorption from the old cuticle, which may promote the storage of a part of this calcium within the midgut posterior caeca. The calcium levels fall after exuviation to late postmolt to the low basal levels of intermolt; this may reflect the imbalance between the rates of calcification of the newly secreted cuticle and uptake of calcium within the posterior caeca. Administration of sal…

Oxygen isotope composition of North American bobcat (Lynx rufus) and puma (Puma concolor) bone phosphate: implications for provenance and climate rec…

2015

Feline carnivores are threatened by illegal wildlife trade. Tracing the provenance of unknown felid tissues via stable isotope analysis could provide important information in wildlife crime investigations. The oxygen isotope composition of mammalian skeletal phosphate (δ(18)Op) is widely applied to trace the origin of animal remains and to reconstruct migratory patterns in palaeontological, archaeological, ecological and wildlife forensic applications. Teeth and bones of terrestrial mammals form at constant body temperature in isotope equilibrium with body water, which is predominantly controlled by ingested meteoric water (δ(18)Ow) that varies systematically with latitude, altitude and cli…

Evaluating the need for acid treatment prior to d13C and d15N analysis of freshwater fish scales: effects of varying scale mineral content, lake prod…

2010

Prevalence of carotid artery calcifications among 2,500 digital panoramic radiographs of an adult Brazilian population

2018

Background The aim of the present study was to analyze the epidemiological data of digital panoramic radiographs revealing suggestive images of carotid artery calcifications (CAC) from a Northeast Brazilian population. Material and Methods A cross-sectional retrospective study was conducted with 2,500 digital panoramic radiographs obtained from a single imaging reference center in Northeast Brazil. Images from individuals of both sexes and older than 18 years were included and those that did not cover the region of cervical vertebrae or presented low radiographic quality were excluded. Data were analyzed regarding prevalence, location (bilateral, right or left), sex, and age using the Chi-s…

Effect of bioglass on growth and biomineralization of SaOS-2 cells in hydrogel after 3D cell bioprinting.

2014

We investigated the effect of bioglass (bioactive glass) on growth and mineralization of bone-related SaOS-2 cells, encapsulated into a printable and biodegradable alginate/gelatine hydrogel. The hydrogel was supplemented either with polyphosphate (polyP), administered as polyP • Ca2+-complex, or silica, or as biosilica that had been enzymatically prepared from ortho-silicate by silicatein. These hydrogels, together with SaOS-2 cells, were bioprinted to computer-designed scaffolds. The results revealed that bioglass (nano)particles, with a size of 55 nm and a molar ratio of SiO2 : CaO : P2O5 of 55 : 40 : 5, did not affect the growth of the encapsulated cells. If silica, biosilica, or polyP …

Premature aging in bone of fish from a highly polluted marine area

2015

Fish species have attracted considerable interest in studies assessing biological responses to environmental contaminants. In this study, the attention has been focussed on fishbone of selected fish species from a highly polluted marine area, Augusta Bay (Italy, Central Mediterranean) to evaluate if toxicant elements had an effect on the mineralogical structure of bones, although macroscopic deformations were not evident. In particular, an attempt was made to evaluate if bone mineral features, such as crystallinity, mineral maturity and carbonate/phosphate mineral content, determined by XR-Diffraction and FT-IR Spectroscopy, suffered negative effects due to trace element levels in fishbone,…

Calcification is not the Achilles' heel of cold-water corals in an acidifying ocean

2015

Ocean acidification is thought to be a major threat to coral reefs: laboratory evidence and CO2 seep research has shown adverse effects on many coral species, although a few are resilient. There are concerns that cold-water corals are even more vulnerable as they live in areas where aragonite saturation (?ara) is lower than in the tropics and is falling rapidly due to CO2 emissions. Here, we provide laboratory evidence that net (gross calcification minus dissolution) and gross calcification rates of three common cold-water corals, Caryophyllia smithii, Dendrophyllia cornigera, and Desmophyllum dianthus, are not affected by pCO2 levels expected for 2100 (pCO2 1058 ?atm, ?ara 1.29), and nor a…

Mediterranean carbonate system dynamics and planktonic biocalcification during the last 19,000 years

2013

Lithiasis and Spontaneous Hemobilia

2015

Learning objectives Background Findings and procedure details Conclusion Personal information References

A Microcalcification Detection System in Mammograms based on ANN Clustering

2018

Breast cancer is one of the leading causes to women mortality in the world. Clustered microcalcifications (MCs) in mammograms can be an important early sign of breast cancer, the detection is important to prevent and treat the disease. In this work, we present a novel method for the detection of MCs in mammograms which consists of regions of Interest (ROIs) segmentation, based on a spatial filter that allows the detection of small and large microcalcifications, clustering and classification of MCs by Artificial Neural Network. The system has been tested on a public dataset of digital images and compared with previous approaches. The results demonstrate that the proposed approach could achie…