A Plasma Biochemical Analysis of Acute Lead Poisoning in a Rat Model by Chemometrics-Based Fourier Transform Infrared Spectroscopy: An Exploratory Study

Pb2+ Ion Sensors Employing Gold Etching Process: Comparative Investigation on Au Nanorods and Au Nanotriangles

The leaching phenomenon of gold (Au) nanomaterials by Pb2+ ions in the presence of 2-mercaptoethanol (2-ME) and thiosulfate (S2O32- ion) has been systematically applied to a Pb2+ ion sensor. To further investigate the role of Pb2+ ions in sensors containing Au nanomaterials, we revisited the leaching conditions for Au nanorods and compared them with the results for Au nanotriangles. By monitoring the etching rate, it was revealed that Pb2+ ions were important for the acceleration of the etching rate mainly driven by 2-ME and S2O32- pairs, and nanomolar detection of Pb2+ ions were shown to be promoted through this catalytic effect. Using the etchant, the overall size of the Au nanorods decreased but showed an unusual red-shift in UV-Vis spectrum indicating increase of aspect ratio. Indeed, the length of Au nanorods decreased by 9.4% with the width decreasing by 17.4% over a 30-min reaction time. On the other hand, the Au nanotriangles with both flat sides surrounded mostly by dense Au{111} planes showed ordinary blue-shift in UV-Vis spectrum as the length of one side was reduced by 21.3%. By observing the changes in the two types of Au nanomaterials, we inferred that there was facet-dependent alloy formation with lead, and this difference resulted in Au nanotriangles showing good sensitivity, but lower detection limits compared to the Au nanorods.

Detection Techniques for Lead Ions in Water: A Review

Lead pollution has increasingly become the focus of environmental pollution, which is a great harm to the ecological environment and human health. Strict control of the emission of lead pollutants and accurate monitoring of lead are very important. The lead ion detection technologies are introduced here, including spectrophotometry, electrochemical method, atomic absorption spectrometry, and other detection methods, and the methods' applicability, the advantages, and disadvantages are discussed. The detection limits of voltammetry and atomic absorption spectrometry are as low as 0.1 μg/L, and those of atomic absorption spectrometry are as low as 2 μg/L. The detection limit of photometry is higher (0.01 mg/L), but this method can be achieved in most laboratories. The application of different extraction pretreatment technologies in lead ion detection is introduced. The new technologies develop at home and abroad, such as precious metal nanogold technology, paper microfluidic technology, fluorescence molecular probe technology, spectroscopy, and other emerging technologies in recent years, are reviewed, and the principle and application of various technologies are expounded.

A novel mushroom (Auricularia polytricha) glycoprotein protects against lead-induced hepatoxicity, promotes lead adsorption, inhibits organ accumulation of lead, upregulates detoxifying proteins, and enhances immunoregulation in rats

Introduction

Lead is a ubiquitous environmental and industrial pollutant. Its nonbiodegradable toxicity induces a plethora of human diseases. A novel bioactive glycoprotein containing 1.15% carbohydrate, with the ability of adsorbing lead and effecting detoxification, has been purified from Auricularia polytricha and designated as APL. Besides, its mechanisms related to regulation of hepatic metabolic derangements at the proteome level were analyzed in this study.

Methods

Chromatographic techniques were utilized to purify APL in the current study. For investigating the protective effects of APL, Sprague-Dawley rats were given daily intraperitoneal injections of lead acetate for establishment of an animal model, and different dosages of APL were gastrically irrigated for study of protection from lead detoxification. Liver samples were prepared for proteomic analyses to explore the detoxification mechanisms.

Results and discussion

The detoxifying glycoprotein APL displayed unique molecular properties with molecular weight of 252-kDa, was isolated from fruiting bodies of the edible fungus A. polytricha. The serum concentrations of lead and the liver function biomarkers aspartate and alanine aminotransferases were significantly (p<0.05) improved after APL treatment, as well as following treatment with the positive control EDTA (300 mg/kg body weight). Likewise, results on lead residue showed that the clearance ratios of the liver and kidneys were respectively 44.5% and 18.1% at the dosage of APL 160 mg/kg, which was even better than the corresponding data for EDTA. Proteomics disclosed that 351 proteins were differentially expressed following lead exposure and the expression levels of 41 proteins enriched in pathways mainly involved in cell detoxification and immune regulation were normalized after treatment with APL-H. The results signify that APL ameliorates lead-induced hepatic injury by positive regulation of immune processing, and suggest that APL can be applied as a therapeutic intervention of lead poisoning in clinical practice. This report represents the first demonstration of the protective action of a novel mushroom protein on lead-elicited hepatic toxicity.

Calf Thymus DNA Exposed to Quinacrine at Physiological Temperatures and pH Acquires Immunogenicity: A Threat for Long Term Quinacrine Therapy

Quinacrine is an Acridine derivative with two potentially reactive groups; a diamino butyl side chain and an Acridine ring both capable of interacting with DNA but in different ways. This is an antimalarial drug approved by FDA for long term clinical trials and for the treatment of other diseases as well. The study evaluates the physicochemical interactions of quinacrine with DNA (calf thymus DNA) through characterizations of quinacrine DNA adduct (Q-DNA) by various techniques. It was observed that quinacrine induces stability in the structure of DNA, as the onset of melting was found to be increased by 6 °C in the melting temperature profile of Q-DNA supported by other data obtained during study, deviation from the native structure of DNA was analyzed by FTIR that showed specific shifts in the region of 1707-1400 cm-1.The study also probed the antigenicity of Q-DNA compared to its non antigenic native counterpart (N-DNA), by using both as antigens in female New Zealand White rabbits. Q-DNA was found to be antigenic with antibody titer > 1:6400. IgG was isolated and characterized to check for binding specificity. These antibodies were found to be promiscuous capable of cross reacting with other cellular molecules. Analysis of the data obtained suggested that intracellular accumulation of quinacrine and its ability to cross nucleus may allow the drug to interact with DNA. This may bring about significant structural perturbations in the macromolecule triggering an immunogenic response at the site where anti Q-DNA antibody and Q-DNA complex accumulates.

Use of Fourier-Transform Infrared Spectroscopy (FT-IR) for Monitoring Experimental Helicobacter pylori Infection and Related Inflammatory Response in Guinea Pig Model

Infections due to Gram-negative bacteria Helicobacter pylori may result in humans having gastritis, gastric or duodenal ulcer, and even gastric cancer. Investigation of quantitative changes of soluble biomarkers, correlating with H. pylori infection, is a promising tool for monitoring the course of infection and inflammatory response. The aim of this study was to determine, using an experimental model of H. pylori infection in guinea pigs, the specific characteristics of infrared spectra (IR) of sera from H. pylori infected (40) vs. uninfected (20) guinea pigs. The H. pylori status was confirmed by histological, molecular, and serological examination. The IR spectra were measured using a Fourier-transform (FT)-IR spectrometer Spectrum 400 (PerkinElmer) within the range of wavenumbers 3000–750 cm⁻¹ and converted to first derivative spectra. Ten wavenumbers correlated with H. pylori infection, based on the chi-square test, were selected for a K-nearest neighbors (k-NN) algorithm. The wavenumbers correlating with infection were identified in the W2 and W3 windows associated mainly with proteins and in the W4 window related to nucleic acids and hydrocarbons. The k-NN for detection of H. pylori infection has been developed based on chemometric data. Using this model, animals were classified as infected with H. pylori with 100% specificity and 97% sensitivity. To summarize, the IR spectroscopy and k-NN algorithm are useful for monitoring experimental H. pylori infection and related inflammatory response in guinea pig model and may be considered for application in humans.

Lead Poisoning in Opium-Addicted Subjects, Its Correlation with Pyrimidine 5'-Nucleotidase Activity and Liver Function Tests

BACKGROUND

Lead may be added to the opium by drug smugglers. It can cause elevated blood lead level (BLL) in opium-addicted patients. Erythrocyte pyrimidine 5'-nucleotidase (P5N) activity is susceptible to high BLL. The aim of this study was to find out whether opium-addicted patients show erythropathy and elevated liver enzymes explainable by high BLL and decreased P5N activity.

METHODS

Forty orally opium-addicted subjects and 40 normal healthy volunteers were enrolled in this study. BLL was measured in whole blood specimens using atomic absorption spectrometry instrumentation. Enzymatic activity, protein amount of P5N, and erythrocyte purine/pyrimidine ratio were determined. Blood films were analyzed for the presence of basophilic stippling of red cells and hemolytic anemia. The level of liver function enzymes was measured.

RESULTS

The mean BLL for opium-addicted patients was significantly higher than control group (P < 0.001). On the contrary, P5N activity showed a valid decrease in opium-addicted patients when compared with control group (P < 0.001). In line with repressed P5N activity, erythrocyte purine/pyrimidine ratio in patients was lower than control group (P < 0.001). A statistically significant reverse correlation was found between BLL and P5N activity (P < 0.05, r = -0.85). The prevalence of both basophilic stippling (P < 0.001, z = 6.62) and hemolytic anemia (P < 0.001, z = 6.52) in study population was significantly associated with elevated BLL. We could not find any significant correlation between serum level of liver enzymes and BLL.

CONCLUSIONS

Opium-addicted patients in Tehran, Iran, are at high risk of lead poisoning which may result in hematologic problems and possibly hepatic damage.