scholarly journals Analytical geochemistry in the service of medicine: An experimental study of urinary stones from Northern Greece

2017 ◽  
Vol 47 (2) ◽  
pp. 818
Author(s):  
A. Iordanidis ◽  
J. Garcia-Guinea
Keyword(s):  
Stone Formation ◽  
Environmental Scanning Electron Microscopy ◽  
Analytical Techniques ◽  
Urinary Stone ◽  
Urinary Stones ◽  
Environmental Scanning ◽  
X Ray Diffraction ◽  
Northern Greece ◽  
Mineralogical Characteristics

Knowledge of the precise human biomineral composition may allow physicians to recommend an appropriate prophylactic therapy for the patient and thus prevent or delay the stone recurrence. The present study focuses on the application of complementary analytical techniques to the characterization of human urinary stones. Several gallbladder and renal stone samples were obtained from patients dwelling in areas of northern Greece. A comprehensive analytical study took place, employing the following, common in analytical geochemistry, techniques: Environmental Scanning Electron Microscopy (ESEM) coupled to Energy Dispersive System (EDS), X-Ray Diffraction (XRD), thermogravimetry (TG), μRaman spectroscopy and Cathodoluminescence (CL). A detailed determination of morphological, micro-structural, molecular, chemical and mineralogical characteristics of the urinary stone samples was achieved. It was evident by our study the application of powerful analytical techniques could substantially help the medical advisors to ascribe a medical treatment of diseases related to stone formation.

scholarly journals Characterisation of Mycenaean and matt-painted pottery from Alani, ancient upper Macedonia, Greece

2007 ◽  
Vol 40 (4) ◽  
pp. 1796
Author(s):  
A. Iordanidis ◽  
J. Garcia-Guinea ◽  
G. Karamitrou-Mentessidi
Keyword(s):  
Bronze Age ◽  
Environmental Scanning Electron Microscopy ◽  
Environmental Scanning ◽  
X Ray Diffraction ◽  
Northern Greece ◽  
X Ray ◽  
Ancient Pottery ◽  
Mineralogical Characteristics ◽  
Pottery Sherds ◽  
Painted Pottery

Several analytical methods were applied for the study of ancient pottery from Aiani, ancient upper Macedonia, northern Greece. Mycenaean and matt-painted pottery sherds, dated form Late Bronze age, were analysed with the help of X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF) and Environmental Scanning Electron Microscopy, coupled with Energy Dispersive X-ray system (ESEM-EDX). Morphological, chemical and mineralogical characteristics of both types of ancient pottery indicated a rather local provenance, thus strengthening the hypothesis of the co-existence of Mycenaean and Dorian pottery workshops in the region, during Late Bronze period

Low-voltage SEM of urinary stones

1993 ◽  
Vol 51 ◽  
pp. 416-417
Author(s):  
Peter Rez ◽  
Michail Reilly
Keyword(s):  
Low Voltage ◽  
Analytical Techniques ◽  
Urinary Stone ◽  
Urinary Stones ◽  
X Ray Diffraction ◽  
Stone Formers ◽  
Calcium Oxalates ◽  
Recurrent Stone ◽  
Recurrent Stone Formers

Urinary stones are predominantly composed of calcium oxalate and calcium apatite while a minority of stones are formed from uric acid. The oxalate stones occur with greatest frequency, mainly in the form of the monohydrate (whellewite) with some dihydrate (wedellite) present. Despite many years of extensive research, the mechanisms for kidney stone nucleation and growth are still unknown. In particular the urine from recurrent stone formers, and the urine from those who do not form stones, does not show large differences in concentration of either calcium or oxalate ions. Recent work has emphasised the role of possible “inhibitors” or “promoters” in the growth of urinary stones though the quest for these substances remains elusive. Much effort has been devoted to the study of crystallization of calcium oxalates in an attempt to understand nucleation, aggregation and growth as a function of pH and the presence of possible promoters or inhibitors.Many analytical techniques have been applied to urinary stone analysis with X-ray diffraction, wet chemistry and infrared spectroscopy being the most successful for routine characterisation.

Environmental scanning electron microscopy of fresh human gallstones reveals new morphologies of precipitated calcium salts

1992 ◽  
Vol 50 (2) ◽  
pp. 1322-1323
Author(s):  
Howard S. Kaufman ◽  
Keith D. Lillemoe ◽  
John T. Mastovich ◽  
Henry A. Pitt
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Environmental Scanning Electron Microscopy ◽  
Environmental Scanning ◽  
X Ray Diffraction ◽  
Calcium Salts ◽  
Cholesterol Gallstones ◽  
X Ray ◽  
Ca Carbonate ◽  
Scanning Electron

Gallstones contain precipitated cholesterol, calcium salts, and proteins. Calcium (Ca) bilirubinate, palmitate, phosphate, and carbonate occurring in gallstones have variable morphologies but characteristic windowless energy dispersive x-ray (EDX) spectra. Previous studies of gallstone microstructure and composition using scanning electron microscopy (SEM) with EDX have been limited to dehydrated samples. In this state, Ca bilirubinates appear as either glassy masses, which predominate in black pigment stones, or as clusters, which are found mostly in cholesterol gallstones. The three polymorphs of Ca carbonate, calcite, vaterite, and aragonite, have been identified in gallstones by x-ray diffraction, however; the morphologies of these crystals vary in the literature. The purpose of this experiment was to study fresh gallstones by environmental SEM (ESEM) to determine if dehydration affects gallstone Ca salt morphology.Gallstones and bile were obtained fresh at cholecystectomy from 6 patients. To prevent dehydration, stones were stored in bile at 37°C. All samples were studied within 4 days of procurement.

Use of non-contrast computed tomography determined urinary stone fragility in predicting the outcome of extracorporeal shockwave lithotripsy treatment: a single-center study

2020 ◽  
Vol 14 (2) ◽  
pp. 59-63
Author(s):  
Athar Hameed ◽  
Khazir Hayyat Gondal
Keyword(s):  
Shock Waves ◽  
Renal Stone ◽  
Plain Film ◽  
Renal Stones ◽  
Renal Calculus ◽  
Urinary Stone ◽  
Stone Disease ◽  
Urinary Stones ◽  
Fisher Exact Test

Background: Renal stones represent a common urological pathology where standard treatment advised is ESWL in current practice. However, NCCT based determination of stone fragility may help to predict the outcome of ESWL treatment, hence optimizing its clinical use. Therefore, this study evaluated the role of NCCT determined urinary stone fragility in predicting the outcome of ESWL treatment in local clinical settings. Patients and methods: One hundred patients with single renal calculus of 0.6-2 cm in size were included. NCCT based determination of stone fragility in HU units was done for all patients. Patients were then subjected to ESWL, with a maximum of 3000 shock waves given per ESWL session. Plain film and/or ultrasonography was used to monitor ESWL treatment progress with a final NCCT evaluation at 12 weeks to determine the clearance of the calculi for each patient. Association of NCCT based stone fragility and outcome of ESWL was statistically analyzed using Fisher exact test. Results: The mean age of the patients was 37.7 ± 10.9 years with 54% being male. Decreasing stone fragility on NCCT (high = <500HU, moderate = 500-1000HU, and high = 1000HU) required more number and intensity of ESWL sessions (1-2 visits and 3000-6000 shock waves for high stone fragility group, 3-5 visits and 7000-18000 shock waves for the moderate group, and 6 visits and >18000 shock waves for low fragility group, respectively) necessary for clearance of urinary stones (p<0.001). In 98% of patients, the clearance of urinary stones was excellent. Conclusion: Renal stone patients with NCCT determined high and moderate stone fragility show an optimal response after ESWL treatment, whereas, for low fragility renal stones attenuative treatment like percutaneous nephrolithotomy and/or ureteroscopy should be considered instead of ESWL. This approach can enable patient stratification before ESWL therapy ensuring better clinical management of the renal stone disease.

scholarly journals Proteus mirabilis Urease: Unsuspected Non-Enzymatic Properties Relevant to Pathogenicity

2021 ◽  
Vol 22 (13) ◽  
pp. 7205
Author(s):  
Matheus V. C. Grahl ◽  
Augusto F. Uberti ◽  
Valquiria Broll ◽  
Paula Bacaicoa-Caruso ◽  
Evelin F. Meirelles ◽  
...  
Keyword(s):  
Proteus Mirabilis ◽  
Stone Formation ◽  
Cell Types ◽  
Bioinformatic Analysis ◽  
Urinary Stone ◽  
Enzymatic Properties ◽  
Hek293 Cells ◽  
Urinary Stones ◽  
Isolated Cells ◽  
Tnf Α

Infection by Proteus mirabilis causes urinary stones and catheter incrustation due to ammonia formed by urease (PMU), one of its virulence factors. Non-enzymatic properties, such as pro-inflammatory and neurotoxic activities, were previously reported for distinct ureases, including that of the gastric pathogen Helicobacter pylori. Here, PMU was assayed on isolated cells to evaluate its non-enzymatic properties. Purified PMU (nanomolar range) was tested in human (platelets, HEK293 and SH-SY5Y) cells, and in murine microglia (BV-2). PMU promoted platelet aggregation. It did not affect cellular viability and no ammonia was detected in the cultures’ supernatants. PMU-treated HEK293 cells acquired a pro-inflammatory phenotype, producing reactive oxygen species (ROS) and cytokines IL-1β and TNF-α. SH-SY5Y cells stimulated with PMU showed high levels of intracellular Ca2+ and ROS production, but unlike BV-2 cells, SH-SY5Y did not synthesize TNF-α and IL-1β. Texas Red-labeled PMU was found in the cytoplasm and in the nucleus of all cell types. Bioinformatic analysis revealed two bipartite nuclear localization sequences in PMU. We have shown that PMU, besides urinary stone formation, can potentially contribute in other ways to pathogenesis. Our data suggest that PMU triggers pro-inflammatory effects and may affect cells beyond the renal system, indicating a possible role in extra-urinary diseases.

scholarly journals Nutrition and Kidney Stone Disease

Nutrients ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1917
Author(s):  
Roswitha Siener
Keyword(s):  
Kidney Stone ◽  
Fluid Intake ◽  
Stone Formation ◽  
Urinary Stone ◽  
Stone Disease ◽  
Urinary Stones ◽  
Dietary Therapy ◽  
Effective Prevention ◽  
Kidney Stone Disease ◽  
Nutrition And Diet

The prevalence of kidney stone disease is increasing worldwide. The recurrence rate of urinary stones is estimated to be up to 50%. Nephrolithiasis is associated with increased risk of chronic and end stage kidney disease. Diet composition is considered to play a crucial role in urinary stone formation. There is strong evidence that an inadequate fluid intake is the major dietary risk factor for urolithiasis. While the benefit of high fluid intake has been confirmed, the effect of different beverages, such as tap water, mineral water, fruit juices, soft drinks, tea and coffee, are debated. Other nutritional factors, including dietary protein, carbohydrates, oxalate, calcium and sodium chloride can also modulate the urinary risk profile and contribute to the risk of kidney stone formation. The assessment of nutritional risk factors is an essential component in the specific dietary therapy of kidney stone patients. An appropriate dietary intervention can contribute to the effective prevention of recurrent stones and reduce the burden of invasive surgical procedures for the treatment of urinary stone disease. This narrative review has intended to provide a comprehensive and updated overview on the role of nutrition and diet in kidney stone disease.

scholarly journals Iterative regularity and parent-offspring growth mold of stable grain array in bismuth silicate micro-crystals

2011 ◽  
Vol 43 (1) ◽  
pp. 105-112
Author(s):  
Z.G. Zhang ◽  
X.F. Wang ◽  
Q.Q. Tian
Keyword(s):  
Environmental Scanning Electron Microscopy ◽  
Morphological Properties ◽  
Environmental Scanning ◽  
X Ray Diffraction ◽  
Bismuth Silicate ◽  
X Ray ◽  
Offspring Growth ◽  
Line Spacing ◽  
Array Structure ◽  
Sintering Method

Bismuth silicate micro-crystals with grain array structure were prepared by sintering method under atmosphere pressure. The samples were characterized for structural and surface morphological properties by X-ray diffraction (XRD) and Environmental scanning electron microscopy (ESEM). The result shows that stable grain arrays grow by iterative mode. If a stable grain array eliminates, a new stable grain array will generate. In a stable parent array, an offspring array may generate after the corresponding partial elimination of its parent array. If one part of an offspring array stops growing, it will be as a new parent array, and then its offspring grain array will create. The sum of the lengths of an offspring array and the corresponding eliminated part of its parent array is equal to the length of the next eliminated part of its parent array. It means the growth rate of an offspring array is equal to that of the corresponding survived part of its parent array. There is a highly correlation between grain array length and average grain line spacing. It means that larger average grain line spacing corresponds to the stable grain array with lager length. When average grain line spacing increases 1?m, the corresponding array length will increase approximately 7.6?m.

The structure and chemical layering of Proterozoic stromatolites in the Mojave Desert

2015 ◽  
Vol 14 (3) ◽  
pp. 517-526 ◽  
Author(s):  
Susanne Douglas ◽  
Meredith E. Perry ◽  
William J. Abbey ◽  
Zuki Tanaka ◽  
Bin Chen ◽  
...  
Keyword(s):  
Elemental Analysis ◽  
Mojave Desert ◽  
Environmental Scanning Electron Microscopy ◽  
Xrd Analysis ◽  
Environmental Scanning ◽  
X Ray Diffraction ◽  
Mars Rover ◽  
X Ray ◽  
High K ◽  
Representative Samples

AbstractThe Proterozoic carbonate stromatolites of the Pahrump Group from the Crystal Spring formation exhibit interesting layering patterns. In continuous vertical formations, there are sections of chevron-shaped stromatolites alternating with sections of simple horizontal layering. This apparent cycle of stromatolite formation and lack of formation repeats several times over a vertical distance of at least 30 m at the locality investigated. Small representative samples from each layer were taken and analysed using X-ray diffraction (XRD), X-ray fluorescence (XRF), environmental scanning electron microscopy – energy dispersive X-ray spectrometry, and were optically analysed in thin section. Optical and spectroscopic analyses of stromatolite and of non-stromatolite samples were undertaken with the objective of determining the differences between them. Elemental analysis of samples from within each of the four stromatolite layers and the four intervening layers shows that the two types of layers are chemically and mineralogically distinct. In the layers that contain stromatolites the Ca/Si ratio is high; in layers without stromatolites the Ca/Si ratio is low. In the high Si layers, both K and Al are positively correlated with the presence and levels of Si. This, together with XRD analysis, suggested a high K-feldspar (microcline) content in the non-stromatolitic layers. This variation between these two types of rocks could be due to changes in biological growth rates in an otherwise uniform environment or variations in detrital influx and the resultant impact on biology. The current analysis does not allow us to choose between these two alternatives. A Mars rover would have adequate resolution to image these structures and instrumentation capable of conducting a similar elemental analysis.

Evaluation of Pulsed Laser Deposited Li4Ti5O12 Thin Film Anodes by CV and EIS

2013 ◽  
Vol 743-744 ◽  
pp. 13-19 ◽  
Author(s):  
Jian Qiu Deng ◽  
Zhou Guang Lu ◽  
Chi Yuen Chung ◽  
Zhong Min Wang ◽  
Huai Ying Zhou
Keyword(s):  
Thin Film ◽  
Electrochemical Impedance ◽  
Discharge Rate ◽  
Pulsed Laser ◽  
Environmental Scanning Electron Microscopy ◽  
Cycling Performance ◽  
Laser Deposition ◽  
Environmental Scanning ◽  
X Ray Diffraction ◽  
X Ray

Li4Ti5O12thin film anodes were prepared successfully using pulsed laser deposition technique. The thin films were characterized by X-ray diffraction and environmental scanning electron microscopy. The effects of thickness and scan rate on the electrochemical properties of Li4Ti5O12thin film electrodes were discussed in detail. The thin film anodes deliver favorable capacity and excellent cycling performance. The discharge capacity maintains at 141 mAhg-1after 20 cycles at 1C charge-discharge rate for the thin film anodes deposited for 20 minutes. The charge-transfer resistances were also investigated by electrochemical impedance spectroscopy.

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