Marcin Mikulewicz

Hair analysis in health assessment

BACKGROUND Hair analysis is used for estimation of the nutritional status of individuals. In the present work, a systematic review on the relation between the mineral composition of hair and the physical or mental disorders is discussed. Detailed information of examined populations, methods of sample preparations and analytical techniques are presented. METHODS A systematic literature search in four electronic databases Scopus, PubMed, Web of Science and Medline (from 1997 to 2012/01/31) for English language articles was performed. In addition, a reference list and manual search was undertaken. RESULTS The following number of studies was included: 66. Most of the authors reported that there exists a correlation between deficiency or excess of some elements in hair and occurrence of some diseases, such as: autism, cancer, hypertension, myocardial infarction, kidney disease and diabetes mellitus. However, not all results were consistent. CONCLUSIONS Most of the authors concluded that the profile of hair mineral imbalance might be useful as a diagnostic tool for the early diagnosis of many diseases. However, it seems that there is a need to standardize sample preparation procedures, in particular washing and mineralization methods.

Release of Metal Ions from Orthodontic Appliances by In Vitro Studies: A Systematic Literature Review

In the present work, a systematic literature review on release of metal ions from orthodontic appliances under in vitro conditions is described. Detailed and schematic analysis of used materials and applied methods (immersion media, incubation time, temperature, and analytical techniques) is provided. The PubMed search identified 40 studies, among which eight met the selection criteria. One additional study was included in the review. All the authors agreed that the doses of released metal ions were far below the toxic level and the dietary intake. Although the concentrations of metal ions in immersion media greatly differed, the general conclusions were coherent. It must be underlined that the main disadvantage of in vitro tests was that the experimental setup did not reflect in vivo conditions, e.g., the presence of biofilm, which grows on the surface of the materials in oral cavity. The presence and activity of microflora to a large extent is responsible for the process of corrosion, in particular, biodeterioration. The further scheme of in vitro research should incorporate changeable conditions of oral cavity environment (pH, dynamic conditions—saliva flow) and the presence of microbiological flora (microbiological attack) in the experimental design and, first of all, the real proportions of appliance elements.

Reference values of elements in human hair: A systematic review

BACKGROUND The lack of systematic review on reference values of elements in human hair with the consideration of methodological approach. The absence of worldwide accepted and implemented universal reference ranges causes that hair mineral analysis has not become yet a reliable and useful method of assessment of nutritional status and exposure of individuals. OBJECTIVES Systematic review of reference values of elements in human hair. DATA SOURCES PubMed, ISI Web of Knowledge, Scopus. STUDY ELIGIBILITY CRITERIA Humans, hair mineral analysis, elements or minerals, reference values, original studies. RESULTS The number of studies screened and assessed for eligibility was 52. Eventually, included in the review were 5 papers. The studies report reference ranges for the content of elements in hair: macroelements, microelements, toxic elements and other elements. Reference ranges were elaborated for different populations in the years 2000-2012. The analytical methodology differed, in particular sample preparation, digestion and analysis (ICP-AES, ICP-MS). Consequently, the levels of hair minerals reported as reference values varied. CONCLUSIONS It is necessary to elaborate the standard procedures and furtherly validate hair mineral analysis and deliver detailed methodology. Only then it would be possible to provide meaningful reference ranges and take advantage of the potential that lies in Hair Mineral Analysis as a medical diagnostic technique.

Cytocompatibility of Medical Biomaterials Containing Nickel by Osteoblasts: a Systematic Literature Review

The present review is based on a survey of 21 studies on the cytocompatibility of medical biomaterials containing nickel, as assessed by cell culture of human and animal osteoblasts or osteoblast-like cells. Among the biomaterials evaluated were stainless steel, NiTi alloys, pure Ni, Ti, and other pure metals. The materials were either commercially available, prepared by the authors, or implanted by various techniques to generate a protective layer of oxides, nitrides, acetylides. The observation that the layers significantly reduced the initial release of metal ions and increased cytocompatibility was confirmed in cell culture experiments. Physical and chemical characterization of the materials was performed. This included, e.g., surface characterization (roughness, wettability, corrosion behavior, quantity of released ions, microhardness, and characterization of passivation layer). Cytocompatibility tests of the materials were conducted in the cultures of human or animal osteoblasts and osteoblast-like cells. The following assays were carried out: cell proliferation and viability test, adhesion test, morphology (by fluorescent microscopy or SEM). Also phenotypic and genotypic markers were investigated. In the majority of works, it was found that the most cytocompatible materials were stainless steel and NiTi alloy. Pure Ni was rendered and less cytocompatible. All the papers confirmed that the consequence of the formation of protective layers was in significant increase of cytocompatibility of the materials. This indicates the possible further modifications of the manufacturing process (formation of the passivation layer).

Release of metal ions from fixed orthodontic appliance: An in vitro study in continuous flow system

OBJECTIVE To evaluate the release of metal ions from fixed orthodontic appliances. MATERIALS AND METHODS A new system for in vitro testing of dental materials was constructed and consisted of a thermostatic glass reactor that enabled immersion of the studied material. Experimental conditions reflected the human oral cavity, with a temperature of 37°C and a saliva flow rate of 0.5mL/min. The simulated fixed orthodontic appliance made of stainless steel was evaluated. Sampling was performed at several time points during the 28-day study, and the metal ion concentration was determined by inductively coupled plasma optical emission spectrometry. RESULTS The total mass of released metal ions from the appliance during 4 weeks of the experiment was as follows nickel 18.7 μg, chromium 5.47 μg, copper 31.3 μg. CONCLUSIONS The estimated doses of nickel, chromium, and copper determined by extrapolation of experimental data released during the treatment period were far below the toxic dose to humans. This shows that orthodontic treatment might not be a significant source of exposure to these metal ions.

Exposure to metals from orthodontic appliances by hair mineral analysis

The aim of the present work was to investigate the exposure of patients to metals released from orthodontic appliances in situ. The paper reports the results of biocompatibility studies of orthodontic appliances by an in vivo method using hair sampled from the group of patients (N = 28) and a control group (N = 18). The mean content of metals (Ni, Cr, Mn, Fe) in hair that were hypothesized to be systemically absorbed from stainless steel, was provided. The highest difference between the groups was found for Ni (39% higher level in hair of patients), Mn (18%), Fe (4.1%), Cr (2.5%), as calculated by a new dimensionless metal release coefficient (α). The second coefficient defined in the present work (β) corresponded to the difference in the mean content of elements between the groups. The coefficient was the highest for Fe, subsequently Ni, Mn and Cr. None of the differences was statistically significant. For each group and a given element, ranges between 10th and 90th percentile were determined. The upper value of the range differed the mostly between the groups for Ni (82.5%) showing that stainless steel of orthodontic appliance can be the source of exposure to this element. The difference was also identified for Mn (26.5%). For Cr and Fe, the lower value of the range was elevated. It was noted that 22% of patients undergoing orthodontic treatment had elevated levels of Ni in hair. A correlation matrix between the content of the elements in hair was calculated. Statistically significant correlations were found between Cr and Fe, showing similar sources of exposure. Multiple regression analysis showed the dependence of Ni content (dependent variable) on the level of Co and Mg (synergism) and V (antagonism).

The release of metal ions from orthodontic appliances animal tests.

OBJECTIVE To investigate the release of metal ions from an orthodontic appliance in tests on animals (pigs). MATERIALS AND METHODS An animal test was conducted on 24 pigs divided equally into an experimental and a control group. In total, 12 sets of experimental orthodontic plates were surgically inserted into pig snouts in the experimental group for 6 months. Noninvasive matrices (hair [0, 3, and 6 months]) and invasive matrices (kidneys, liver, lungs, aorta, and oral mucosa) were collected for multi-elemental analysis (inductively coupled plasma optical emission spectrometry) from the experimental and control groups. RESULTS The greatest differences in the content of toxic metals were found in the aorta (Ni level was 4.8 times higher in experimental than in the control group), in the cheek (Ni 3.5 times higher), and in the hair sampled after 3 months (Cr 3.4 times higher). CONCLUSIONS The obtained data indicate that the products of corrosion have passed into selected tissues of pigs; however, the doses of toxic metal ions released from the appliance did not reach toxic levels.

Supercritical Algal Extracts: A Source of Biologically Active Compounds from Nature

The paper discusses the potential applicability of the process of supercritical fluid extraction (SFE) in the production of algal extracts with the consideration of the process conditions and yields. State of the art in the research on solvent-free isolation of biologically active compounds from the biomass of algae was presented. Various aspects related with the properties of useful compounds found in cells of microalgae and macroalgae were discussed, including their potential applications as the natural components of plant protection products (biostimulants and bioregulators), dietary feed and food supplements, and pharmaceuticals. Analytical methods of determination of the natural compounds derived from algae were discussed. Algal extracts produced by SFE process enable obtaining a solvent-free concentrate of biologically active compounds; however, detailed economic analysis, as well as elaboration of products standardization procedures, is required in order to implement the products in the market.

Exposure to nickel by hair mineral analysis

The aim of the present work was to investigate the exposure to nickel from various sources by investigation of mineral composition of human scalp hair. The research was carried out on hair sampled from subjects, including 87 males and 178 females (22 ± 2 years). The samples of hair were analyzed by ICP-OES. The effect of several factors on nickel content in hair was examined: lifestyle habits (e.g. hair coloring, hair spray, hair straighteners, hair drier, drugs); dietary factors (e.g. yoghurts, blue cheese, lettuce, lemon, mushroom, egg, butter); other (e.g. solarium, cigarette smoking, tap water pipes, tinned food, PVC foil, photocopier, amalgam filling). These outcomes were reached by linking the results of nickel level in hair with the results of questionnaire survey. Basing on the results it can be concluded that exposure to nickel ions can occur from different sources: lifestyle, eating habits and environmental exposure.

Do soft drinks affect metal ions release from orthodontic appliances

OBJECTIVE The effect of orange juice and Coca Cola(®) on the release of metal ions from fixed orthodontic appliances. MATERIALS AND METHODS A continuous flow system designed for in vitro testing of orthodontic appliances was used. Orange juice/Coca Cola(®) was flowing through the system alternately with artificial saliva for 5.5 and 18.5h, respectively. The collected samples underwent a multielemental ICP-OES analysis in order to determine the metal ions release pattern in time. RESULTS The total mass of ions released from the appliance into orange juice and Coca Cola(®) (respectively) during the experiment was calculated (μg): Ni (15.33; 37.75), Cr (3.604; 1.052), Fe (48.42; ≥ 156.1), Cu (57.87, 32.91), Mn (9.164; 41.16), Mo (9.999; 30.12), and Cd (0.5967; 2.173). CONCLUSIONS It was found that orange juice did not intensify the release of metal ions from orthodontic appliances, whereas Coca Cola(®) caused increased release of Ni ions.