A new method of urinary stone analysis by batik histochemical staining of thin sections.

Thin sections of urinary calculi are prepared by petrographic methods using Araldite as the mounting medium. By covering the remaining part of the section with wax, an exposed segment of the section is stained by a histochemical technique. By the process of dewaxing and rewaxing, successive adjacent segments are stained by GBHA, Von Kossa, Schultz, and titan yellow methods for calcium oxalate, apatite, uric acid and urates, and magnesium in magnesium ammonium phosphate, respectively. If desired, matrix in additional segments is stained with PAS and aqueous toluidine blue. Microscopic examination of each layer through all the stained segments of a stone section reveals its chemical nature. Thus the chemical composition, morphology, and spatial distribution of the crystalline and matrix constituents of thin sections of urinary calculi are simultaneously revealed in situ.     

A New Method of Urinary Stone Analysis by Batik Histochemical Staining of thin Sections

Thin sections of urinary calculi are prepared by petrographic methods using Araldite of the mounting medium. By covering the remaining put of the don with wax, an exposed segment of the section is stained by a histochemical technique. By the process of dewaxing ad rewaxing, successive adjacent segments are stained by GBHA, Von Kossa, schultz, and titan yellow methods for calcium oxalate, apatite, uric acid and urates, and magnesium in magnesium ammonium phosphate, respectively. If desired, matrix in additional segments is stained with PAS and aqueous toluidine blue. Microscopic examination of each layer through all the stained segments of a stone section reveals its chemical nature. Thus the chemical composition, morphology, and spatial distribution of the crystalline and matrix constituents of thin sections of urinary calculi are simultaneously revealed in situ.     

Composition and Distribution of Elements and Ultrastructural Topography of a Human Cardiac Calculus

Trace elements (TEs) may contribute to the formation of calculi or stones or be involved in the aetiopathogenesis of stone diseases. The compositions and spatial distribution of elements from the inner nucleus to outer crust of the cardiac calculus were investigated by energy-dispersive X-ray fluorescence (EDXRF) spectrometer. The surface topograph, distribution map of elements, elemental and chemical compositions were also determined by environmental scanning electron microscope (ESEM)–energy-dispersive X-ray (EDX) analysis. Twenty-five elements were identifiable from 18 positions on the cardiac calculus by EDXRF spectrometer, in which the highest concentrations of toxic TEs (Ni, Pt, Hg, Sn, Pb, W, Au, Al, Si) and higher levels of essential TEs (Ca, Sr, Cr, P) were detected. A moderate positive Pearson’s correlation between TEs concentrations of Mg, Ca or P and location differences from centre to periphery in the cardiac calculus was observed. A positive correlation was also found for Ca/Zn and Ca/Cu, indicating the gradual increase of calcium concentration from inner nucleus to outer crust of cardiac calculus. The drop-like nodules/crystals on the surface of petrous part of cardiac calculus were observed from ESEM analysis. ESEM–EDX analysis determined the calculus to be predominantly composed of calcium hydroxyapatite and cholesterol, as indicated by the petrous surface and drop-like nodules/crystals, respectively. This composition was confirmed using a portable Raman analyser. The spatial distribution analysis indicated a gradual increase in Mg, P and Ca concentrations from the inner nucleus to the outer crust of the cardiac calculus. The major chemical compositions of calcium hydroxyapatite and cholesterol were detected on this cardiac calculus.     

Mineralization of pristine chitosan film through biomimetic process

The biomineralization of pristine chitosan film without any prior surface treatment was evaluated by immersing the film in simulated body fluid (SBF) at 37 °C for 3 weeks. The film was prepared by solvent casting method using chitosan of known degree of deacetylation (DD). The formation of the hydroxyapatite (HA) phase on the film surface after immersion was studied periodically by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), energy dispersive X-ray analysis (EDX) and scanning electron microscopy (SEM) methods. The electron micrographs showed the morphology of the deposited apatite as small globules appearing uniformly throughout the films surfaces. The Ca/P ratio of the apatite was found to increase with increase in immersion time and approaching towards the stoichiometric value of the HA phase. The mineralized chitosan film could be of promising support to hard tissue regeneration.     

Hydrochlorothiazide, allopurinol and magnesium oxide in the treatment of recurrent calcium urolithiasis]

The study aimed at presenting own experience in prevention of new urinary calculi in 18 patients with metabolically active calcium urolithiasis treated with hydrochlorothiazide in daily doses of 100 mg (group I) for 2 years, and in 6 patients with the same disease treated with magnesium oxide in daily doses 300 mg twice a day (group II) for average period of 10 months. In 9 patients a new calculus was formed during the treatment with hydrochlorothiazide, in 7 patients no recurrence was noted, and in 2 remaining patients the results were controversial (coral calculus). Therefore, patients were subdivided into group Ia (failure of hydrochlorothiazide therapy), and group Ib (no recurrence noted). Hydrochlorothiazide did not lead to the stable decrease in the saturation of the urine with calcium oxalate in group Ia whereas in group Ib (without recurrence of urolithiasis) the content of calcium oxalate in the urine was significantly lower than that in group Ia after a 2-year treatment with hydrochlorothiazide (p < 0.01) Recurrence of the disease was seen only in one patient of group II, i.e. treated with magnesium oxide. The treatment of the recurrent calcium urolithiasis is justified and efficient in those patients in whom therapy decreases the content of calcium oxalate in the urine.     

Urogenital sinus calculi in a sand tiger shark (Odontaspis taurus)

Two calculi were found in the urogenital sinus of a 70 kg female sand tiger shark (Odontaspis taurus). The calculi were white in color, rough surfaced, and spherical in shape. Crystallographic examination revealed that they were composed of magnesium ammonium phosphate hexahydrate (80% struvite) and calcium phosphate (15% carbonate apatite). Approximately 5% of the stone matrix consisted of blood and protein and a distinct bacterial nidus was not present microscopically.     

SOME ASPECTS OF THE MANAGEMENT OF BILATERAL CALCULUS DISEASE OF THE KIDNEY

In the diagnosis of bilateral calculus disease of the kidneys, it is important to differentiate between cystine, uric acid, calcium oxalate and phosphate renal lithiasis. Methods for distinguishing one from another are described.Dietary therapy is the method of choice for cystine and uric acid lithiasis.In calcium and phosphate urolithiasis, dietary therapy is a very useful adjunct. It must be regulated by careful studies of its effect on urinary calcium precipitability, a new test for which is described based upon the demonstration of the existence of two forms of calcium in the urine.Irrigation therapy for calcium phosphate and phosphate lithiasis is briefly discussed.Surgical therapy for large renal phosphatic calculi is discussed to show how considerations of renal counterbalance and urinary calcium, magnesium and phosphate excretion through damaged kidney substances influence the surgical plan in each case.     

Novel technique for internal structure and elemental distribution analyses of granular sludge from reactors for wastewater treatment

A novel technique for internal structure and elemental distribution analyses of granular sludge is presented. Sludge samples were freeze-dried and embedded in epoxy resin to form a module, which were then ground and polished to obtain sequential cross-sections. The cross-sections were analyzed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). SEM observations showed that one granule was formed having several cores with different inorganic minerals, rather than a single core. EDX results indicate that the main elements of the granules are O, Ca, Mg, and P. In addition, the distribution areas of calcium and magnesium in the granule do not coincide.     

A comparative study of clinically well-characterized human atherosclerotic plaques with histological, chemical, and ultrastructural methods

Atherosclerotic plaques (six cases) with well-documented clinical history were analysed using histology, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy, infrared spectroscopy (IR), thermogravimetry (TG), and high-resolution synchrotron X-ray diffraction. All samples contained about 60-70 wt% biological carbonated apatite (in dry state) in a nanocrystalline form with particle sizes of about 20 nm. Structurally, there are strong similarities to bone mineral. Ultrastructural investigations documented typical calcospherites, mineralisation processes starting at collagen fibrils and ring-shaped crystalline mineralised structures. There were no significant ultrastructural or chemical differences between the calcifications of individual patients.     

Structural and chemical characterization of inorganic deposits in calcified human mitral valve

X-ray diffraction, i.r. absorption, and chemical analyses have been carried out on the mineral deposits of calcified human mitral valves and glutaraldehyde-preserved porcine aortic grafts. The mineral deposits isolated from highly calcified mitral valves and porcine aortic grafts are constituted of type B-carbonate apatite. Magnesium substituted beta-tricalcium phosphate is present, together with an apatitic phase similar to dahllite, in the ashes of poorly calcified mitral valves. The contraction of the unit cell of beta-tricalcium phosphate due to magnesium incorporation is compared with the variation of the lattice constants of synthetic beta-tricalcium phosphate at different degree of magnesium substitution for calcium. The results reveal the important role of magnesium on the calcification of human valves. In fact, the apatitic phase deposited at the beginning of the calcification process, when there is a high magnesium content, converts completely into beta-tricalcium phosphate by heat treatment at 1,000 degrees C. On the other hand, when the calcification becomes massive, magnesium content appears highly reduced, and the deposited apatitic phase is characterized by a high thermal stability.     

多孔beta-磷酸三钙与磷灰石复合材料的制备及其细胞相容性研究

综合运用三维凝胶叠层法和发泡法制备了多孔β-磷酸三钙支架。将多孔支架在1．5倍模拟体液中浸泡14天,得到材料1;或者将其在氢氧化钠溶液中浸泡4天,再在1．5倍模拟体液中浸泡14天,得到材料2。测定了两种材料的物理性能,讨论了类骨磷灰石层对材料矿物组成及其显微结构等的影响。将两组材料分别与成骨前体细胞在体外复合培养,观察和测定了细胞的形态和增殖情况。结果表明复合材料的主要成分为β-磷酸三钙,表面具有结构不完整的含有碳酸磷灰石的类骨磷灰石,成骨细胞能在两组材料上正常粘附和增殖,而且材料2上的细胞粘附情况更好,说明多孔β-磷酸三钙与磷灰石的复合材料有望成为一种有应用前景的骨修复材料和骨组织工程支架材料。     

Preliminary study on the correlation between the trace Mn2+ and the calcite polymorph in gallstones containing calcium carbonate from the northeast China via electron spin resonance

Gallstones containing calcium carbonate (GCCC) from the northeast China were analyzed using X-ray diffraction (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and electron spin resonance (ESR). The sextet signal arising from the allowed transitions of the trace Mn²⁺ ions in GCCC was found to be ESR-detectable and strong. The XRD technique revealed the crystal habit of calcite in GCCC. Of the three polymorphs of calcium carbonate, no calcite was present as a solitary crystallization form, accompanied by aragonite or vaterite or both. The sextet ESR signal and the (104) main XRD peak at 2θ = ∼29.4° were employed as two probes to explore the relationship between trace Mn²⁺ and calcite. The Mn content can be considered as an indicator of the amount of calcite in GCCC because of the existence of a correlation between Mn²⁺ and calcite. The correlation between Mn²⁺ and calcite, the relation between the levels of Mn²⁺ and the type of gallstones, the structural preference of Mn²⁺ to the calcite polymorph, and the influence of dietary habits on calcite in calcium carbonate gallstones are discussed.     

Biocompatible DCPD Coating Formed on AZ91D Magnesium Alloy by Chemical Deposition and Its Corrosion Behaviors in SBF

Bioactive calcium phosphate coatings were prepared on AZ91D magnesium alloy in phosphating solution in order to im- prove the corrosion resistance of the magnesium alloy in Simulated Body Fluid （SBF）. The surface morphologies and compo- sitions of the calcium phosphate coatings deposited in the phosphating bath with different compositions were investigated by Scanning Electron Microscopy （SEM） with Energy Dispersive Spectrometer （EDS） and X-ray Diffraction （XRD）. Results showed that the calcium phosphate coating was mainly composed of dicalcium phosphate dihydrate （CaHPO4o2H20, DCPD）, with Ca/P ratio of approximately 1 ： 1. The corrosion resistance was evaluated by acid drop, electrochemical polarization, elec- trochemical impedance spectroscopy and immersion tests. The dense and uniform calcium phosphate coating obtained from the optimal phosphating bath can greatly decrease the corrosion rate and hydrogen evolution rate of AZ91D magnesium alloy in SBE     

Initial stages of microbiologically influenced tarnishing on titanium after 20 months of immersion in freshwater

This paper studies the initial stages of iridescent tarnishes on titanium heat exchanger tubes in contact with running freshwater on the river Tagus in Spain for up to 20 months. Electrochemical impedance spectroscopy (EIS), scanning electron microscopy [(SEM with energy dispersive X-ray (EDX)] and X-ray photoelectron spectroscopy (XPS) in conjunction with argon-ion sputtering were the techniques used. The EIS data indicated a capacitive behavior, showing a semicircle that was better defined as the experimental time increased, indicating a decreasing tarnishing resistance of titanium. XPS and EDX results indicated that the main elements identified were calcium, phosphorus, nitrogen, and iron. The amount of these elements was higher on the tarnished titanium specimens than on the untarnished specimens. SEM analysis showed the presence of diatoms in the iridescent tarnishes on titanium tubes.     

Focused ion beam (FIB)/scanning electron microscopy (SEM) in tissue structural research

The focused ion beam (FIB) and scanning electron microscope (SEM) are commonly used in material sciences for imaging and analysis of materials. Over the last decade, the combined FIB/SEM system has proven to be also applicable in the life sciences. We have examined the potential of the focused ion beam/scanning electron microscope system for the investigation of biological tissues of the model organism Porcellio scaber (Crustacea: Isopoda). Tissue from digestive glands was prepared as for conventional SEM or as for transmission electron microscopy (TEM). The samples were transferred into FIB/SEM for FIB milling and an imaging operation. FIB-milled regions were secondary electron imaged, back-scattered electron imaged, or energy dispersive X-ray (EDX) analyzed. Our results demonstrated that FIB/SEM enables simultaneous investigation of sample gross morphology, cell surface characteristics, and subsurface structures. The same FIB-exposed regions were analyzed by EDX to provide basic compositional data. When samples were prepared as for TEM, the information obtained with FIB/SEM is comparable, though at limited magnification, to that obtained from TEM. A combination of imaging, micro-manipulation, and compositional analysis appears of particular interest in the investigation of epithelial tissues, which are subjected to various endogenous and exogenous conditions affecting their structure and function. The FIB/SEM is a promising tool for an overall examination of epithelial tissue under normal, stressed, or pathological conditions.     

A Biological Stone from a Medieval Cemetery in Poland

A review of the literature shows that origination of biological stones as well as their pathogenesis mostly depend on the environmental factors. As a result, the structural spectrum of such calculi and their chemical composition are highly diversified. It is well known that biological stones are formed mostly in the digestive and urinary tracts. However, it has been demonstrated that this kind of stony structure can be also, though rarely, found in circulatory and reproductive systems, skin, mucosa, and tear ducts. Although in palaeopathology, the list of biological stones is enriched by stony tumours and/or discharges, it is very difficult to uncover the small size deposits in excavation material. In the literature such findings, originating from different countries and centuries, are few. The described stone was found among the bones of an adult individual in the medieval cemetery of Gdańsk (Poland). The SEM, X-ray spectrometer and chemical evaluation revealed that it was a bladder calculus.     

Renal Calculi

The pathogenesis of renal calculi is reviewed in general terms followed by the results of investigation of 439 patients with renal calculi studied by the author at Toronto General Hospital over a 13-year period. Abnormalities of probable pathogenetic significance were encountered in 76% of patients. Idiopathic hypercalciuria was encountered in 42% of patients, primary hyperparathyroidism in 11%, urinary infection in 8% and miscellaneous disorders in 8%. The incidence of uric acid stones and cystinuria was 5% and 2% respectively. In the remaining 24% of patients in whom no definite abnormalities were encountered the mean urinary magnesium excretion was less than normal. Of 180 patients with idiopathic hypercalciuria, only 24 were females. In the diagnosis of hyperparathyroidism, the importance of detecting minimal degrees of hypercalcemia is stressed; attention is also drawn to the new observation that the upper limit of normal for serum calcium is slightly lower in females than in males. The efficacy of various measures advocated for the prevention of renal calculi is also reviewed. In the author''s experience the administration of thiazides has been particularly effective in the prevention of calcium stones. Thiazides cause a sustained reduction in urinary calcium excretion and increase in urinary magnesium excretion. These agents also appear to affect the skeleton by diminishing bone resorption and slowing down bone turnover.     

Calcium dynamics in idiopathic calcium stone formers

Ionic calcium, calcium binding sites, and other urinary variables were measured in 58 patients with idiopathic calcium nephrolithiasis and 36 normal subjects. The patients showed higher urinary concentrations of calcium. The mean calcium excretion (mmole/24 hr) was 4.45 +/- 0.56 (+/- 1 SEM) in patients and 2.19 +/- 0.22 (+/- 1 SEM) in normal subjects. This difference was highly significant (P less than 0.001). The mean ionic calcium excretion (mmole/24 hr) was 1.90 +/- 0.21 (+/- 1 SEM) for patients and 0.97 +/- 0.12 (+/- 1 SEM) for control subjects. The normal subjects showed significantly higher (P less than 0.01) concentrations and total excretions of magnesium and citrate. Excretory patterns for sodium, potassium, phosphate, and oxalate were not significantly different. The normal subjects had higher mean urinary concentrations of binding sites for calcium ions (23.2 +/- 4.8 mM) than the patients (18.5 +/- 2.9 mM). However, as the patients had higher urinary volumes the difference in the 24-hr excretion of calcium binding sites was not significant statistically. Out of 58 patients 43 (74%) were hypercalciuric. Twenty patients (46%) were categorized as an absorptive group and one patient as a resorptive type, and for the rest of the patients (51%) the mechanism of hypercalciuria remained unidentified. Only two of the control subjects (5%) were found to be hypercalciuric under calcium restricted diet conditions. Though these "control" subjects excreted a high amount of calcium there was no associated increase in the fraction of the calcium in the ionic form (0.37). Patients, however, still had relatively high fractions of ionic calcium (0.48 +/- 0.03).     

Struvite calculus in the vagina of a bottlenose dolphin (Tursiops truncatus)

On 27 January 2000, a struvite calculus was observed in the vagina during necropsy of a 138-cm-long female bottlenose dolphin (Tursiops truncatus) collected from the Stono River, South Carolina (USA). Vaginal calculi have been reported in other species of cetaceans but not in bottlenose dolphins. Urinary tract infection might have been an underlying cause of the calculus. While urinary tract inflammation was not detected by light microscopic evaluation of sections of the urinary tract, it is conceivable that sufficient time had lapsed following voiding of the calculus through the urethra for urinary tract infection to have resolved. To further define the prevalence and significance of urolithiasis, prosectors of dead stranded marine mammals are encouraged to closely observe their urinary and genital tracts for calculi and to submit them for quantitative analysis.     

Effect of synthesis method and chemical reagents on the structural parameters,particle size,and optical and photoluminescence properties of ZnS nanostructures

In this experimental study, ZnS nanostructures were synthesized using two hydrothermal and co‐precipitation methods with different precursors. Different reagents and precursors were changed to obtain the best product size and morphology. The structure and crystal phase of the products were studied using X‐ray diffraction (XRD) patterns. Some structural parameters were calculated using the XRD results and a product composition was obtained by energy dispersive X‐ray (EDX) analysis and Fourier transform infrared (FT‐IR) spectra to study the chemical composition. The size and morphology of ZnS nanostructures were obtained by scanning electron microscopy (SEM). The optical properties of the synthesized ZnS nanostructures were examined using ultraviolet–visible (UV–Vis) spectra to estimate the optical band gap. Band gap energies were higher than those in the ZnS bulk sample, mainly due to quantum size effects. The photoluminescence (PL) properties of the products were investigated using PL spectra. The results showed the effect of two factors, namely synthesis method and chemical reagents, on the structure parameters, crystallite size, product size and morphology, and optical and PL properties.