Preparation of fingernails for trace element analysis

Serum Zinc Ion Concentration Associated with Coronary Heart Disease: A Systematic Review and Meta-Analysis

Aim

Coronary heart disease is a major cause of mortality in developed and developing countries. Changes in the trace element concentration in the human body are one of the main reasons for the transition of the human body from a healthy to a diseased state. In this meta-analysis, we have studied the relationship between the reduction in serum zinc ion concentration and coronary heart disease.

Methods

We used PubMed and Cochrane (as of June 30, 2021) databases for the literature search. Per the requirements of this systematic review, case-control studies involving serum zinc ion concentration and coronary heart disease were searched, and the quality of the included studies was evaluated before the meta-analysis.

Results

A total of 3,981 cases were found across seven articles. The standard mean deviation (SMD) of serum zinc ion concentration was −0.22 [−0.28, −0.15], z = 6.52, and P < 0.05 indicated that the difference was statistically significant. The forest plot results show that I² = 34% < 50%, and the Q test showed P=0.17 > 0.1. These results suggest a lack of heterogeneity among the selected articles. Results from the funnel chart indicated that this study was free from publication bias.

Conclusion

The results of this meta-analysis reveal that a decrease in serum zinc ion concentration is related to the occurrence of coronary heart disease. Clinically, monitoring the serum zinc ion levels is proven to be of great significance for patients with coronary heart disease.

Comparison between elemental composition of human fingernails of healthy and opium-addicted subjects by laser-induced breakdown spectroscopy

The objective of the present work is to identify differences in elemental fingernail composition between opium-addicted and healthy adult human subjects using laser-induced breakdown spectroscopy. Thirty nails from normal, healthy male subjects and 30 nails from opium-addicted male individuals were analyzed. Measurements on 60 nail samples were carried out, identifying 13 key species including 11 neutral elements and 2 ions. Discriminant Function Analysis (DFA) was used to classify the samples between the two groups. Spectral line intensities of elements including Fe, C, Ti, Mg, Si, Al, Ca, H, K, O, and Na were considered variables in DFA. This analysis demonstrates the efficient discrimination between the two groups. However, the number of samples in this work is not sufficient for a decisive conclusion and further research is needed to generalize this idea.

Investigation of the content and of the distribution of chemical elements in human nails by SRXRF

The purpose of this investigation is to analyze 20 nails in individuals (and several persons) for the definition of how chemical elements distribute from nail to nail. The aim was to determine whether it will be rightful to take only one nail for the elemental analysis for the diagnostic of human state in future or not? Another purpose of the research is to analyze the elemental content of nails in temporal dynamic (in several persons). Analytical determinations of 20 nails of nine donors (healthy persons), nails of both hands and both feet were carried out. The analysis was performed by SRXRF. Symmetry of the elemental distribution in nails of right and left hands and right and left feet was found. The analysis of the distribution of chemical elements on the total area of a nail (55 points) was performed. The nail cutaway reflects adequately the distribution of several chemical elements over the nail plate area. In this study the elemental concentrations in nails of three donors in a 6-month period was determined. This study found the content of the chemical elements in donors' nails changes with time, individually.

Nail calcium and magnesium content in relation to age and bone mineral density

In view of the importance of calcium (Ca) and magnesium (Mg) as major bone components and nutrients controlling bone metabolism, and the ready availability of nail samples for analysis, clippings of fingernails and toenails were analyzed for Ca and Mg. The clippings were dissolved in nitric acid and analysis was done, using atomic absorption spectrophotometry, in 169 women and 115 men between 20 and 80 years of age. Fingernail Ca concentration in men decreased from 927 +/- 50 ppm (mean +/- SEM) in their twenties to 464 +/- 50 ppm in their eighties, with a significant negative correlation with age (r = -0.322; P < 0.0001) and such a negative correlation was also shown in the women (r = -0.269; P = 0.0004). Toenail Ca concentrations also decreased significantly with age in men (r = -0.534; P < 0.0001) and women (r = -0.224; P = 0.0016). Fingernail Mg concentration, in contrast, increased significantly with age in both men (r = 0.209; P = 0.0145) and women (r = 0.280; P < 0.0001), but toenail Mg failed to show significant changes with age in either men or women. Multiple stepwise regression analysis of age and lumbar bone mineral density (LBMD) on fingernail Ca concentration eliminated age before LBMD. In a separate group of 33 women in their sixties, a significant positive correlation was noted between fingernail Ca and LBMD (r = 0.544; P = 0.0016) and between toenail Ca and LBMD (r = 0.399; P = 0.0215). A negative correlation was also noted between fingernail Mg concentration and LBMD (r = -0.389; P = 0.0252). Nail mineral content may be utilized as one of the indicators of bone mineral metabolism.

Ram horn peptone as a source of citric acid production by Aspergillus niger, with a process

The present study deals with the production of citric acid from a ram horn peptone (RHP) by Aspergillus niger NRRL 330. A medium from RHP and a control medium (CM) were compared for citric acid production using A. niger in a batch culture. For this purpose, first, RHP was produced. Ram horns were hydrolyzed by treatment with acids (6 N H(2)SO(4), 6 N HCl) and neutralizing solutions. The amounts of protein, nitrogen, ash, some minerals, total sugars, total lipids and amino acids of the RHP were determined. RHP was compared with peptones with a bacto-tryptone from casein and other peptones. The results from RHP were similar to those of standard peptones. The optimal concentration of RHP for the production of citric acid was found to be 4% (w/w). A medium prepared from 4% RHP was termed ram horn peptone medium (RHPM). In comparison with CM, the content of citric acid in RHPM broth (84 g/l) over 6 days was 35% higher than that in CM broth (62 g/l). These results show that citric acid can be produced efficiently by A. niger from ram horn.

Application of double focusing sector field ICP-MS for multielemental characterization of human hair and nails. Part III. Direct analysis by laser ablation

The capabilities of laser ablation double focusing sector field inductively coupled plasma mass spectrometry for the determination of 55 elements in nails and hair were studied. Quantification was performed by external calibration using in-house matrix-matched standards in tablet form following correction for variations in ablation efficiency by internal standardization using a matrix element (S). For nails, intra-individual long- and short-term chronological variations as well as depth distribution patterns were studied. For the majority of elements tested, significant enrichment was found in the surface of the nail. Element distributions along a hair strand were investigated with a spatial resolution of 2.5 mm.

Single-cell protein production from ram horn hydrolysate by bacteria

Ram horns obtained from the slaughterhouse of Erzurum, Turkey were hydrolyzed by treating with acid (6N-HCl) and ram horn hydrolysate (RHH) was obtained. The hydrolysate was used as substrate to grow Bacillus cereus NRRL B-3711, Bacillus subtilis NRRL NRS-744 and Escherichia coli in batch system at 30 degrees C; air 1.5 v/v/min; stirring 150 rpm. Both RHH and biomass samples were analyzed. The bacterial cells produced in this hydrolysate were found to be rich in total protein (66%, 68% and 71% for E. coli, B. cereus and B. subtilis, respectively). The chemical oxygen demand and biological oxygen demand were reduced significantly by the growth of bacteria. The protein produced contained all essential amino acids for ruminant feed.

X-ray microanalysis of the fingernails in term and preterm infants

The element content of the fingernails of 10 term and 14 preterm infants, clipped for the first time after delivery, was determined by x-ray microanalysis. The results showed a decrease in sulfur and aluminum, and a higher chlorine content in term infants in comparison with preterm ones, the difference being statistically significant. Sodium, potassium, calcium, and zinc content did not differ in the two groups. Copper, iron, magnesium, aluminum, and phosphorus were detected in trace amounts only. Cobalt was not detected in the fingernails of newborns in either group. The elevated content of aluminum in the fingernails of preterm infants may be a clue to the osteopenia observed in these infants.

Measurement of total calcium in biological fluids: flame atomic absorption spectrometry

The measurement of total calcium (CaT) in biological fluids by flame atomic absorption spectroscopy (FAAS) is one of the more accurate yet practical methods available today. With attention to details at every analytical step, the imprecision of FAAS outlined above can be as low as +/- 0.01 mmol/liter at the 2.65 mmol/liter upper reference level of CaT found in the serum of healthy young adults (a CV of 0.4%). The accuracy of FAAS as judged by measurements of NBS/SRM #909, a lyophilized serum material carrying CaT values assigned by isotope dilution mass spectrometry, can be within +/- 1% (recovery of 99-101%) or less in skilled hands. As our brief section on application suggests, FAAS methods for CaT can be adopted to provide rapid and accurate results in many different biological fluids and tissues.