Endogenous Mineral Research Articles

Spatial models as a tool to identify spatial patterns of surficial sediment composition and their contributing factors in the littoral zone of Lake Constance (Germany)

For a lake-wide investigation of littoral surface sediments, we collected approximately 800 samples from Lake Constance along 235 parallel transects of 1 km distance along the shore at water depths of 1, 2, 4 and 8 m. Sediment samples were analyzed for the presence of spatial patterns in mineralogical and granulometric composition and contents of carbon and sulphur, with the purpose of identifying general and lake specific processes that contribute to the observed patterns. In particular, we wanted to test if the general factors known for contributing to littoral sediment composition could be revealed by spatial modeling of a dataset based on a systematic sampling scheme. Explanatory variables for a regression model were derived from GIS-analyses of the dataset, and also from other available data on Lake Constance. Highest levels of variance explained by the model (30–40%) were reached for the parameters calcite, clay minerals, sulphur and inorganic carbon content. Regional patterns in sediment composition, described by the proportion of explained between-transect variance (VE t ) in the model, are explained by up to 70%. The observed east-west gradient of mineralogical sediment composition is ascribed to the respective regional patterns of allogenic and endogenic sources. Allogenic minerals such as clay, dolomite and quartz dominate the littoral surface sediments of the eastern part of the lake and the areas near river mouths. Endogenic minerals like calcite dominate the littoral sediments of the western parts of the lake, reflecting internal process of biogenic carbonate precipitation that corresponds to the distribution patterns of submersed macrophytes (particularly Charophytes).

Organic matter, nutrient content and biological activity in burned and unburned soils of a Mediterranean maquis area of southern Italy

Experimental fires were performed during the summer-drought period in a Mediterranean maquis in the Castel Volturno Nature Reserve in south-western Italy. The two different fuel loads applied (4 kg m−2 and 2 kg m−2) resulted in complete and partial combustion of the vegetation, respectively. Soil organic matter content (SOM), total and available element concentrations (K, Mg, Na, Mn, Fe, Cu, Pb, Cd), microbial carbon, respiration, metabolic quotient (qCO2), and the coefficient of endogenous mineralization (CEM) were measured at intervals in the dry and wet seasons over a period of about 3 years, in burned and adjacent unburned soils. Soil samples (0–5 cm depth) were collected under the cover of Phillyrea angustifolia L., a dominant species in the study area. Both fires induced long-lasting increases in SOM. As indicated by the increase in CEM, part of the accumulated SOM was mineralized in the first 3 months after fire whereas part of the accumulated SOM was instead stable. Both fires increased the total and available fractions of nutrients and trace elements. During the first 3 months after fire, microbial biomass and qCO2 were higher in the burned soils, which were richer in nutrients, but were characterized by harsher environmental conditions compared to unburned soils.

Low levels of endogenous estradiol protect bone mineral density in young postmenopausal women

Objective Low levels of endogenous estrogens may play a role in the protection of bone mineral density (BMD) in healthy postmenopausal women. The aim of this study was to evaluate the effect of endogenous estradiol and testosterone on bone mass in young and older healthy postmenopausal women.Methods The study involved 99 postmenopausal women aged 55–75 years. The BMDs of the lumbar spine, proximal femur and total skeleton were determined. Measurements were taken of serum calcium, bone alkaline phosphatase, Crosslaps, estradiol, estrone, sex hormone binding globulin, testosterone, bioavailable testosterone and urine calcium. Estradiol was measured using a sensitive assay with a lower detection limit at 5 pg/ml.Results A multivariate analysis showed that the BMD of the lumbar spine was significantly predicted by estradiol (p < 0.05), and testosterone (p < 0.0001). Likewise, testosterone was found to be an independent predictor of the BMD of the total femur (p < 0.001) and the total skeleton (p < 0.001). The population was divided into two groups: ⩽ 65 (Group 1) and > 65 years (Group 2) of age and also stratified according to estradiol levels: > 10 and ⩽ 10 pg/ml. Significant differences in BMD were found in women in Group 1 in whom estradiol levels higher than 10 pg/ml were associated with a higher BMD of the lumbar spine ( + 14%, p < 0.01), proximal femur ( + 6%, p < 0.05) and total skeleton ( + 7%, p < 0.05) compared with women with estradiol levels below 10 pg/ml. Bone alkaline phosphatase levels (p < 0.05) and serum Crosslaps (not significant) were lower in women in Group 1 with a level of estradiol more than 10 pg/ml.Conclusion Endogenous estradiol levels higher than 10 pg/ml and testosterone protected bone mass in healthy postmenopausal women under 65 years of age. These results were not observed in the group of older women.

Evidence for a Serum Factor That Initiates the Re-calcification of Demineralized Bone

The present studies show for the first time that demineralized bone re-calcifies rapidly when incubated at 37 degrees C in rat serum: re-calcification can be demonstrated by Alizarin Red and von Kossa stains, by depletion of serum calcium, and by uptake of calcium and phosphate by bone matrix. Re-calcification is specific for the type I collagen matrix structures that were calcified in the original bone, with no evidence for calcification in periosteum or cartilage. Re-calcification ceases when the amount of calcium and phosphate introduced into the matrix is comparable to that present in the original bone prior to demineralization, and the re-calcified bone is palpably hard. Re-calcified bone mineral is comparable to the original bone mineral in calcium to phosphate ratio and in Fourier transform infrared and x-ray diffraction spectra. The serum activity responsible for re-calcification is sufficiently potent that the addition of only 1.5% serum to Dulbecco's modified Eagle's medium causes bone re-calcification. This putative serum calcification factor has an apparent molecular mass of 55-150 kDa and is inactivated by trypsin or chymotrypsin. The serum calcification factor must act on bone for 12 h before re-calcification can be detected by Alizarin Red or von Kossa staining and before the subsequent growth of calcification will occur in the absence of serum. The speed, matrix-type specificity, and extent of the serum-induced re-calcification of demineralized bone suggest that the serum calcification factor identified in these studies may participate in the normal calcification of bone.

The effects of phytase and phytic acid on the loss of endogenous amino acids and minerals from broiler chickens

1. The effects of myo-inositol hexaphosphate (IP6) and phytase (EC 3.1.3.26) on the excretion of endogenous compounds were investigated using growing broiler chickens. 2. A total of 32 female Ross broilers were used in a precision feeding assay involving a 2×2 factorial arrangement of treatments. The materials administered were glucose, glucose + 1000 units of phytase activity (FTU), glucose + 1 g of IP6 and glucose + 1 g of IP6 + 1000 FTU. Excreta were collected quantitatively over a 48-h period following intubation of the test materials. The excretion of nitrogen, amino acids, minerals, sialic acid and phytate phosphorus was determined. 3. The ingestion of 1 g of IP6 by broilers increased the excretion of endogenous nitrogen, amino acids, iron, sodium, sulphur and sialic acid compared with birds fed on glucose. Supplementation of IP6 with exogenous phytase reduced the excretion of endogenous amino acids, calcium, sodium, phytate phosphorus and sialic acid compared with birds fed IP6. 4. It can be concluded that IP6 increases the excretion of endogenous minerals and amino acids in broiler chickens. Part of the beneficial effects of the addition of exogenous phytases to the diets of poultry appears to be mediated through a reduction in endogenous losses of these nutrients.

Mechanical advantage of defects healed with demineralized bone matrix over autogenous bone graft

Purpose of study: The purpose of this investigation was to compare the mechanical stiffness and strength of healed, grafted defects using either the classical method of autogenous bone graft or demineralized bone matrix.Methods used: Critical 2-cm defects were created in the ulnas of 75 6-month-old male New Zealand White Rabbits (3.5 to 4.0 kg). Defects were treated with approximately 1 cc of graft material: demineralized bone matrix (DBM) plug, DBM + bone marrow (BM), devitalized DBM (dDBM), dDBM + BM, BM, empty or autogenous bone graft (ABG). Animals were radiographed at 0, 3, 6, 9 and at sacrifice at 12 weeks. Sixty-nine rabbits completed the study. The six deaths were the result of surgical complications. Only grafts that were graded as a union were mechanically tested. The radius transected and constructs were tested in torsion to failure. The torsional stiffness and maximum failure torque for each group were compared by analysis of variance with a pairwise comparison test using a Bonferroni adjustment.of findings: The radiographic findings at 12 weeks showed complete bridging of the defect in the DBM and DBM + BM groups. In contrast, healing was not as complete in the dDBM-treated defects. Defects treated with dDBM and bone marrow did considerably better. The BM group displayed complete bridging but without the uniform surface contour seen with the DBM groups. Defects treated with ABG were bridged, although difficult to analyze radiographically because of the endogenous mineral present within the graft. There was no statistical difference between the union rates except for the dDBM and empty groups. The torsional stiffness of the DBM + BM group was twice that of ABG (p<.01). There were no differences found in the maximum torque.Relationship between findings and existing knowledge: This study has shown that treatment of defects with a structural osteoinductive/osteoconductive scaffold, such as a DBM matrix plug in the presence of bone marrow, results in mechanically stronger bone at 12 weeks than defects treated with ABG alone. Although these results were obtained in a long bone model, they are consistent with Boden's results in a rabbit spine fusion model using structural DBM scaffolds and autograft, and suggest bone marrow would be useful adjunct in enhancing spine fusion.Overall significance of findings: In a clearly definable model, we were able to show superior material properties in comparison to the classical standard, ABG.Disclosures: No disclosures.Conflict of interest: Celeste Abjornson, grant research support; Joseph Lane, grant research support, Osteotech

Biochemical indicators of bone metabolic activity in buffalo (Bubalus bubalis) during late pregnancy and early lactation.

Blood levels of calcium, inorganic phosphorus, magnesium, osteocalcin, intact parathyroid hormone, calcitonin, alkaline phosphatase activity, creatinine and thyroid hormones were estimated in 10 healthy buffalo during late pregnancy (30, 15 days and 7 days before calving), within 12 h after calving and 7-15-30-45 and 60 days after calving. The almost constant serum levels of calcium, phosphorus, intact parathyroid hormone, and the low calcitonin concentration indicate that these buffalo need to utilize only a little of their endogenous mineral resources. Bone-turnover could be demonstrated by variations in the serum levels of osteocalcin and alkaline phosphatase activity. A study of these bone markers could be useful for other research purposes and for future clinical application in pathological conditions.

Electrical transport of endogenous mineral ions in green sapwood of Pinus sylvestris L. (Scots pine)

Electrical transport of endogenous mineral ions in green sapwood of Pinus sylvestris L. (Scots pine)

Electrical transport of endogenous mineral ions in green sapwood ofPinus sylvestris L. (Scots pine)

The relative migration of the major endogenous ions (K+, Ca2+ Mg2+, Na+, Cl− in green sapwood ofPinus sylvestris L. was measured in a modified Hittorf transference cell. The transference numbers obtained gave the fractions of the current carried by these ions when an electric field was applied across the wood samples under the conditions used.

Cadmium Binding Capacity of Cocoa and Isolated Total Dietary Fibre under Physiological pH Conditions

Cadmium binding capacity of cocoa and isolated total dietary fibre (TDF) was investigated in vitro under simulated physiological pH conditions. The effect of Cd 2+ retention on the bioavailability of essential endogenous minerals was also studied. The sample was mixed with buffered Cd 2+ solution and, after equilibration, the residue was separated for quantitative measurement of soluble Cd 2+ in the supernatant. Cocoa exhibited a high affinity for Cd 2+ in solution. The amount of bound Cd 2+ rose with increasing metal concentration and pH. TDF was the major fraction responsible for binding of Cd 2+ by cocoa. Phytate was probably another important cause of the decrease of Cd 2+ solubility. The addition of various concentrations of Cd 2+ to cocoa and TDF was shown to affect the solubility of endogenous minerals. When Cd 2+ was bound by TDF there was a marked increase in the availability of endogenous Fe, Zn, Ca and Mg, specially at duodenal pH conditions.

Nutritional Implications of Molt in Male Canvasbacks: Variation in Nutrient Reserves and Digestive Tract Morphology

Body composition and gut morphology of molting male Canvasbacks (Aythya valisineria) were investigated in central Alberta from termination of breeding activities until fall migration (May-October) in 1989-1990. During this postreproductive period, male Canvasbacks underwent prebasic, down, and partial prealternate molts. Protein, lipid, and mineral dynamics were analyzed to determine if male Canvasbacks relied on endogenous nutrient reserves to meet increased nutritional demands during molt. In addition, mass and length of digestive organs were analyzed to document changes in the digestive tract that could provide endogenous protein (i.e., via muscle tissue catabolism) and/or possibly enhance exogenous nutrient assimilation for molt. Ingesta-free body mass of male Canvasbacks reached its annual minima during remigial molt (x = 973.5 g) and fluctuated primarily in response to storage and catabolism of lipids. Body composition data indicated little reliance on endogenous fat, protein, and mineral to satisfy nutrient requirements for molt. Lipid reserves were not accumulated prior to molt, but instead were metabolized from arrival on molting areas through mid-remigial molt. Premigratory lipogenesis started during mid-remigial growth and occurred simultaneous to elevated molt intensity, indicating that energetic requirements for molt were met exogenously. Despite the relative stability of total body protein during postreproductive molts, there were marked shifts in the distribution of muscle tissue in molting birds. Pectoral muscles atrophied from arrival on molting habitat through mid-remigial molt, concurrent with hypertrophy of leg and some digestive tract tissues. Increased mass of the digestive tract during remigial molt originated principally from growth of the gizzard. The digestive tract returned to its original mass as birds regained the ability to fly and their diet reverted back to foods with lower fiber content. Because postreproductive molts were extended over six months, male Canvasbacks had relatively low daily nutritional demands that could be met by dietary intake.

Nutrient Constituents from Eight Lines of Naked Seed Squash (Cucurbita pepo L.)

Seeds from eight lines of naked seed squash (Cucurbita pepo L.) were evaluated for their proximate analysis, amino acid and fatty acid compositions, and mineral content. Moisture content was not significantly different (P < 0.05) among seed types. Protein values were significantly different among seed types and ranged from 37.1 ± 0.45% to 44.4 ± 0.45%. Oil content was high in all seeds and varied from 34.5 ± 0.42% to 43.6 ± 0.06%. Carbohydrates, calculated by difference, varied significantly among seeds. Ash values ranged between 5.1 ± 0.04% and 6.3 ± 0.10%. Energy levels were from 549 ± 3 to 598 ± 1 kcal/100 g. Amino acid patterns were similar among the seed lines. Cysteine and methionine contents were low. Fatty acid composition varied significantly (P < 0.05) among the seeds of selected lines. Oleic acid was significantly the most concentrated (46.6 ± 0.15% to 60.4 ± 0.19%) followed by linoleic (9.6 ± 0.16% to 27.9 ± 0.15%) and palmitic acid (12.8 ± 0.17% to 15.8 ± 0.56%). With the exception of magnesium and manganese, all other endogenous mineral contents varied significantly among seed samples. Potassium, magnesium, and calcium were the most prevalent minerals, respectively. Keywords: Naked seed squash; chemical composition; Cucurbita pepo L.

In Vitro Binding Capacity of Wheat Bran, Rice Bran, and Oat Fiber for Ca, Mg, Cu, and Zn Alone and in Different Combinations

Wheat bran (WB), rice bran (RB), and oat fiber (OF) were analyzed for their proximate constituents and mineral content and evaluated for their binding capacity for calcium (Ca), magnesium (Mg), copper (Cu), and zinc (Zn). Protein, soluble and insoluble dietary fiber, and endogenous mineral contents varied significantly among the three dietary fiber sources. With the exception of Mg, in higher concentration in RB, WB contained significantly (P < 0.05) more endogenous Ca, Cu, and Zn than RB or OF. Overall, WB bound significantly more Ca and Mg (alone or combined with other minerals) than RB and OF, respectively. OF bound more Cu than RB or WB. Zn (alone or in the presence of other minerals) was bound more strongly in WB and RB than OF. Re-acid washing stripped most of the bound minerals from the dietary fiber sources. Keywords: Mineral binding; wheat bran; rice bran; oat fiber; dietary fiber

Use of sheep maintained by intragastric infusion as a model for studying the endogenous loss of phosphorus in ruminants

Mature sheep fitted with a rumen cannula and an abomasal catheter were used to evaluate whether sheep maintained by intragastric infusion could be used as a model for studying minimum endogenous phosporus loss in ruminants. In control periods the sheep received 1·29 g phosphorus day −1 by infusion and maintained phosphorus balance. The withdrawal of phosphorus from the infusate led to a reduction in the excretion of phosphorus to 6·4 mg kg liveweight −1 day −1, a level lower than that currently used to estimate maintenance phosphorus requirements. However, salivary phosphorus secretion, based on rumen phosphorus outflow, averaged only about 1·2 g day −1, a level which would be considered insufficient to meet rumen microbial requirements in a normally fed animal. Allowing the sheep access to a small amount of roughage, although contributing little additional phosphorus, greatly increased salivary phosphorus flow and increased their endogenous excretion of phosphorus to levels close to those used to estimate maintenance requirements. These results suggest that this technique may offer an alternative way of measuring minimum endogenous mineral loss to those currently in use.

Fluoride Modulates the Inhibition of in Vitro Hydroxyapatite Crystal Growth by Small Dentin Proteoglycan: Relevance to Dental Calculus

Glycosaminoglycan constituents of the periodontium have been detected in supragingival and subgingival dental calculus. They are polyanionic heteropolysaccharides containing -COOH and SO3H residues. The non-sulfated hyaluronan is present in supragingival calculus, whereas chondroitin sulfate, dermatan sulfate, and heparan sulfate are detected in subgingival calculus. They are implicated in both ectopic and endogenous mineralization, and have been used in the present study to investigate seeded hydroxyapatite crystal growth, and the influence of fluoride on the process. All glycosaminoglycans examined inhibited crystal growth, with chondroitin-4-sulfate and dermatan sulfate being more effective than the hyaluronan. Fluoride alone enhanced growth and reduced the inhibitory influence of the glycosaminoglycans and the parent proteoglycan, which is a potent inhibitor. The results yield important information on the role of fluoride and proteoglycan in ectopic mineralization.

The availability of iron, zinc and cadmium to rats from composite diets with different cereal grains

Many investigations have been reported in which the effects of varying the concentration of a single factor in grain diets on the availabilities of minerals for absorption have been studied. The purpose of this study in rats was to determine the effects on iron, zinc and cadmium availability of substituting whole grain wheat, oats, barley or rye for iron-supplemented endosperm wheat in a composite diet with one part grain flour and one part non-fat, dried milk with maize oil and vitamins. Iron concentrations varied by a factor of 3 among these diets, zinc by 1.5, cadmium by 5, and both fiber and phytate by a factor of 3.5. The absorption of 59Fe and 65Zn from test meals of the diets and the concentrations of iron, zinc and cadmium in selected tissues and body fluids after five weeks on the grain diets were used as independent measures of the mineral availabilities from these diets. Absorption of iron from endosperm wheat and, to a lesser extent, zinc from oats and rye appears to have been overestimated, most likely due to incomplete exchange of the radioisotopes with the supplemented or endogenous minerals in the grains. The variations in the concentrations of iron and cadmium among the diets were by far the most important factors determining the availabilities of these minerals to the rats. The fractional availabilities of iron and zinc were negatively related to the diet phytate concentration and the fractional availability of cadmium was negatively related to the iron status of the rats. The results indicate that substitution of whole grain wheat for endosperm wheat in the diet will increase cadmium accumulation considerably while substitution of oats, barley or rye should result in nearly the same or lower cadmium accumulation. Due to the low availability of iron in barley and rye, substitution of either grain for iron-supplemented endosperm wheat may compromise iron status. As the diets in this study are similar to baby formulas and breakfast cereals, porridge or a sandwich with milk, the probability that these results in rats are applicable to humans strongly suggests that studies similar to this be carried out in humans.

Aeromagnetic Lineament Study in the Olary Province, South Australia

Several of the most important endogenous mineral deposits are in direct or indirect relation with patterns of deep-seated fracture zones (Kutina, 1974, 1976, Favorskaya, 1977, Kosigin, 1974 and others). Therefore the discovery and study of partial disposition of fractures are important objects for geophysicists. The aeromagnetic lineaments in the Olary Province were studied in an area of 18,000 km 2 in the Willyama Complex area of South Australia. The aeromagnetic lineament directions show four preferred orientations (N30 - 75E; N280 - 319E; N50 - 75E; N75 - 100E), and they are concentrated into some zones of the same orientation. The lineaments themselves coincide in several cases with faults, which have been active since the Precambrian. The distribution of plutonics and mig-matites coincides with these zones, in which patterns of foliation, lineation and minor folds result from shearing along zones.

Proximate Composition and Nutrient Elements in the “Unusual” Algal “Jellies” of Lake Oguta in Southern Nigeria

AbstractThe proximate composition, nutrient and trace elements of the planktonic algal “jellies” of Lake Oguta in Southern Nigeria, are provided as guides to their utilization and control, using flood (rainy) and dry season samples. These “jellies” are an unusual, macroscopic planktonic algal community in the lake, made up mostly of blue‐green algae (Microcystis, Anabaena, Chroococcus) with some green algae (e. g. Spirogyra) and pennate diatoms (e.g. Navicula) rather epiphytic on the mucous jellies of the blue‐green algae. Water content was high (98.2% mean, range 97.5‐99.5%). Ash, protein and fat had values of 41.7 (39.0‐46.2%), 16.9 (15.6‐19.4%), and 2.0 (1.7‐2.1%) respectively. Crude fibre and carbohydrates were high (25.8% and 12.4%). The levels of phosphorus and nitrogen were rather high, so were the major cations whose order of dominance (Ca &gt; K &gt; Mg &gt; Na) differed from that of the lake water. Macronutrients increased in their concentrations during the rainy flood season while the reverse was the case with the micronutrients. Diagenesis of the endogenic minerals rather than anthropogenic factors are thought to be the reason for the seasonal changes in the ionic concentrations. Possible uses of the algal jellies are discussed as well as their control options.

Deep structure and metallogeny of the earth's crust

Considerable experience with integrated geological and geophysical studies has enabled definition of deep crustal structures and, within limits, composition and processes within the deep crust, and to determine their association with metallogeny in the USSR.By means of seismic experiments, stratification of the Earth's crust and the upper mantle to a depth of about 100 km has been revealed. Numerous heat flow data have been compiled. Magneto-telluric soundings made it possible to determine the position of conductive strata in the crust and upper mantle for a number of areas. Gravity surveys coupled with the results of seismic profiling enabled the finding of a number of empirical laws that are useful for investigation into the deep crust. Magnetic data analysis has enabled evaluation of the magnetic layering of the deep crust. Kimberlite and ore provinces can be considered examples of these concepts.For more detailed studies of deep crustal structure the territory of the USSR is the subject of a system of regional investigation of the deep crust and upper mantle. This system is based principally upon a network of interconnected regional profiles (geotraverses) tied to deep and superdeep boreholes. The system includes predicted geophysical observations to control investigation of the geophysical field data. The geotraverse network is the basis for detailed studies within the bounds of petroleum and ore provinces.The most accurate data obtained allows the formation of a crustal model and reveals empirical relationships with metallogeny.Based on the deep crustal structure data a regional oregenesis prediction map has been made. The endogenous mineralization prediction was based on special features of the upper layering of the crust and on data relating to deep crustal permeability zones.

TRENDS IN THE VERTICAL DISTRIBUTION OF ENDOGENOUS MAGNETITE MINERALIZATION

Translated from Zakonomernosti vertikal'nogo razmeshcheniye endogennogo magnetitovogo orudeneniya, Izvestiya AN SSSR, seriya geologicheskaya, 1988, No. 3, pp. 76-85. The author is with the All-Union Research Institute for Mineralization and Geology of Mineral Deposits [BIOGEM], Belgorod. Plots of the cross-sectional area and grade of a dozen deposits show various patterns that suggest exploration techniques appropriate for deposits of different geologic types. The author's studies and literature data are used here to examine the vertical distribution of endogenous mineralization of major econom­ ic types [14]: titanomagnetite, carbonatiteformation apatite-magnetite, contact-metasomatic (skarn-magnetite), and magnomagnetite types. The topic is clearly important for miner­ al exploration. Graphs relating two parameters-the dimensions of the deposit and the mean Fe level of the ore—to depth have been constructed from detailed surveys and mining operations. The zero on the ordinate has been taken as the lowest ground elevation, that is, the upland part, within which the primary pat­ tern has been distorted by uneven erosion has been ignored. Where there may be postmineralization fault movements of considerable am­ plitude, reconstructions of the original posi­ tions were used. The vertical interval of data points was 100 m. The vertical distribution trends for each type can be related to genetic features.