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1.
J Pers Med ; 14(3)2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38541011

ABSTRACT

IgA nephropathy (IgAN) is the most common glomerulonephritis worldwide and a leading cause of chronic kidney disease and renal failure. However, the Bulgarian population has limited epidemiological data and biomarkers for IgAN. In this retrospective monocentric analysis, we investigated all the patients with biopsy-proven IgAN over 10 years in a tertiary Bulgarian institution. From the analysis of 762 kidney biopsies, the diagnosis of primary IgAN was established in 125, with an average age of 35.94 ± 11.91 years. Our study aimed to assess the clinical characteristics, histological features, and potential biomarkers of IgAN in the Bulgarian population. We evaluated parameters such as proteinuria, hematuria, serum creatinine, and glomerular filtration rate (GFR). In fifty IgAN patients and 30 healthy controls, serum levels of Gd-IgA1, IgA, C3, BAFF, and APRIL using ELISA were examined. The results revealed significant differences in serum concentrations of Gd-IgA1 (p < 0.001), Gd-IgA1/IgA (p = 0.022), IgA (p = 0.014), and IgA/C3 (p = 0.047) between patients and controls. However, no correlation was found between Gd-IgA1, IgA, Gd-IgA1/IgA, and IgA/C3 and chronic kidney disease progression. Our study reports evidence of the diagnostic value of Gd-IgA1 and contributes to the understanding of IgAN in the Bulgarian population and suggests potential biomarkers for disease diagnosis and prognosis.

2.
Nutrients ; 15(14)2023 Jul 08.
Article in English | MEDLINE | ID: mdl-37513495

ABSTRACT

In a previous study, large variability in iodine content was found among samples of store brand retail milk at a single time point in a sampling taken from 24 nationwide U.S. locations for the USDA FoodData Central database, but the sampling plan was not designed to detect differences among locations. This follow-up study was carried out to evaluate iodine levels in retail milk across the U.S. over time. Milk samples (2% fat) were collected bimonthly in fourteen locations for one year and analyzed in duplicate. Control materials were used to support accuracy of results and ensure precision across analytical batches. The overall mean and standard error (SE) for iodine concentration were 82.5 (7.0) µg/240 mL serving, which was comparable to the previous national mean [85.0 (5.5) µg/240 mL]. A similar wide range among individual samples was detected (27.9-282 µg/240 mL). For some locations, the mean iodine concentration differed significantly from others, and differed from the national average by amounts ranging from -47 µg to +37 µg per serving. The between-sample range within location was large for some (up to 229 µg/serving) and minimal for others (as little as 13.2 µg/serving). These findings suggest iodine intake from some retail milk supplies could be over- or underestimated relative to the national average, even if the national average is suitable for population-wide intake estimates.


Subject(s)
Iodine , Milk , Animals , Female , Cattle , Milk/chemistry , Follow-Up Studies , Iodine/analysis , Nutritional Status
3.
Sensors (Basel) ; 23(6)2023 Mar 08.
Article in English | MEDLINE | ID: mdl-36991644

ABSTRACT

The popularity of smart sensors and the Internet of Things (IoT) is growing in various fields and applications. Both collect and transfer data to networks. However, due to limited resources, deploying IoT in real-world applications can be challenging. Most of the algorithmic solutions proposed so far to address these challenges were based on linear interval approximations and were developed for resource-constrained microcontroller architectures, i.e., they need buffering of the sensor data and either have a runtime dependency on the segment length or require the sensor inverse response to be analytically known in advance. Our present work proposed a new algorithm for the piecewise-linear approximation of differentiable sensor characteristics with varying algebraic curvature, maintaining the low fixed computational complexity as well as reduced memory requirements, as demonstrated in a test concerning the linearization of the inverse sensor characteristic of type K thermocouple. As before, our error-minimization approach solved the two problems of finding the inverse sensor characteristic and its linearization simultaneously while minimizing the number of points needed to support the characteristic.

4.
Toxicol Sci ; 188(2): 261-275, 2022 07 28.
Article in English | MEDLINE | ID: mdl-35708658

ABSTRACT

Ultrasmall superparamagnetic iron oxide nanoparticles (USPIONs) have been investigated for biomedical applications, including novel contrast agents, magnetic tracers for tumor imaging, targeted drug delivery vehicles, and magneto-mechanical actuators for hyperthermia and thrombolysis. Despite significant progress, recent clinical reports have raised concerns regarding USPION safety related to endothelial cell dysfunction; however, there is limited information on factors contributing to these clinical responses. The influence of USPION surface chemistry on nanoparticle interactions with proteins may impact endothelial cell function leading to adverse responses. Therefore, the goal of this study was to assess the effects of carboxyl-functionalized USPION (CU) or amine-functionalized USPION (AU) (approximately 30 nm diameter) on biological responses in human coronary artery endothelial cells. Increased protein adsorption was observed for AU compared with CU after exposure to serum proteins. Exposure to CU, but not AU, resulted in a concentration-dependent decrease in cell viability and perinuclear accumulation inside cytoplasmic vesicles. Internalization of CU was correlated with endothelial cell functional changes under non-cytotoxic conditions, as evidenced by a marked decreased expression of endothelial-specific adhesion proteins (eg, vascular endothelial-cadherin and platelet endothelial cell adhesion molecule-1) and increased endothelial permeability. Evaluation of downstream signaling indicated endothelial permeability is associated with actin cytoskeleton remodeling, possibly elicited by intracellular events involving reactive oxygen species, calcium ions, and the nanoparticle cellular uptake pathway. This study demonstrated that USPION surface chemistry significantly impacts protein adsorption and endothelial cell uptake, viability, and barrier function. This information will advance the current toxicological profile of USPION and improve development, safety assessment, and clinical outcomes of USPION-enabled medical products.


Subject(s)
Nanoparticles , Protein Corona , Humans , Endothelial Cells/metabolism , Ferric Compounds/metabolism , Magnetic Iron Oxide Nanoparticles , Protein Corona/metabolism
5.
Sensors (Basel) ; 22(3)2022 Jan 26.
Article in English | MEDLINE | ID: mdl-35161693

ABSTRACT

In this work, we introduce and use an innovative approach for adaptive piecewise linear interval approximation of sensor characteristics, which are differentiable functions. The aim is to obtain a discreet type of inverse sensor characteristic, with a predefined maximum approximation error, with minimization of the number of points defining the characteristic, which in turn is related to the possibilities for using microcontrollers with limited energy and memory resources. In this context, the results from the study indicate that to overcome the problems arising from the resource constraints of smart devices, appropriate "lightweight" algorithms are needed that allow efficient connectivity and intelligent management of the measurement processes. The method has two benefits: first, low-cost microcontrollers could be used for hardware implementation of the industrial sensor devices; second, the optimal subdivision of the measurement range reduces the space in the memory of the microcontroller necessary for storage of the parameters of the linearized characteristic. Although the discussed computational examples are aimed at building adaptive approximations for temperature sensors, the algorithm can easily be extended to many other sensor types and can improve the performance of resource-constrained devices. For prescribed maximum approximation error, the inverse sensor characteristic is found directly in the linearized form. Further advantages of the proposed approach are: (i) the maximum error under linearization of the inverse sensor characteristic at all intervals, except in the general case of the last one, is the same; (ii) the approach allows non-uniform distribution of maximum approximation error, i.e., different maximum approximation errors could be assigned to particular intervals; (iii) the approach allows the application to the general type of differentiable sensor characteristics with piecewise concave/convex properties.

6.
Chemosphere ; 294: 133651, 2022 May.
Article in English | MEDLINE | ID: mdl-35065179

ABSTRACT

In this study we present an elemental profile of 46 edible seaweed samples purchased in the United States. The seaweeds were grouped in 13 subgroups/species based on DNA barcoding analysis. The seaweeds were decomposed by microwave accelerated acid digestion followed by quantification of 26 elements by ICP-MS. Elements were grouped into macronutrient (Na, K, Ca, S, Mg and P), essential (Fe, Zn, Mn, V, Cu, Cr, Ni, Mo and Se), non-essential including toxic elements (Sr, Ba, Th, Sn and Sb As, Cd, Pb, U, W and Hg). The highest levels were found for Na and the lowest were for Hg. The elemental profiles depended on the taxonomy of the species and several elements (Fe, Ba, Cr, Pb, W and Th) also exhibited high intraspecies variations, likely due to geographic origin or food processing conditions. Higher Cd and Pb accumulation was observed in wakame, hijiki and nori, with Cd as high 4.05 mg/kg and Pb as high as 2.85 mg/kg in kombu. A study of correlation between the elements using Pearson's coefficients revealed multiple pairs of highly correlated elements in seaweed, as well as triple and quintuple correlations of certain elements.


Subject(s)
Mercury , Seaweed , Trace Elements , Microwaves , Spectrum Analysis , Trace Elements/analysis
7.
Article in English | MEDLINE | ID: mdl-33923240

ABSTRACT

Foreign body giant cell (FBGC) reaction to silicone material in the lymph nodes of patients with silicone breast implants has been documented in the literature, with a number of case reports dating back to 1978. Many of these case reports describe histologic features of silicone lymphadenopathy in regional lymph nodes from patients with multiple sets of different types of implants, including single lumen smooth surface gel, single lumen textured surface gel, single lumen with polyethylene terephthalate patch, single lumen with polyurethane coating, and double lumen smooth surface. Only one other case report described a patient with highly-cohesive breast implants and silicone granulomas of the skin. In this article, we describe a patient with a clinical presentation of systemic sarcoidosis following highly cohesive breast implant placement. Histopathologic analysis and Confocal Laser Raman Microprobe (CLRM) examination were used to confirm the presence of silicone in the axillary lymph node and capsular tissues. This is the first report where chemical spectroscopic mapping has been used to establish and identify the coexistence of Schaumann bodies, consisting of calcium oxalate and calcium phosphate minerals, together with silicone implant material.


Subject(s)
Breast Implantation , Breast Implants , Breast Implants/adverse effects , Granuloma , Humans , Lasers , Silicone Gels/adverse effects
8.
Appl Spectrosc ; 75(6): 661-673, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33231488

ABSTRACT

Many medical devices contain metals that interface with the body. Additionally, embedded metal fragments from military wounds are typically not removed, to avoid the risk of morbidity associated with invasive surgery. The long-term health consequences of many of these materials are not thoroughly understood. To this end, we have exposed rats for up to one year to implanted single-element metal pellets of any one of Al, Co, Cu, Fe, Ni, Pb, Ta, or W. Various tissues were harvested and flash frozen for analysis of their metal distribution. We discuss approaches to most thoroughly and reliably evaluate the distribution of metal in these tissues. The path to the most appropriate analytical technique took us through extensive examination of the tissues using scanning electron microscopy with energy dispersive X-ray spectroscopy (XPS), X-ray photoelectron spectroscopy (XPS), and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Though any one of these methods is highly relied upon in surface chemistry analysis, LA-ICP-MS alone showed presence of metal in the tissue. This information will help build robust methods to bridge the gap in our understanding of biosolubility and distribution of embedded metal throughout the body.


Subject(s)
Laser Therapy , Metals , Animals , Microscopy, Electron, Scanning , Rats , Spectrum Analysis
9.
Chemistry ; 27(2): 669-682, 2021 Jan 07.
Article in English | MEDLINE | ID: mdl-32700787

ABSTRACT

Carbon-based symmetric supercapacitors (SCs) are known for their high power density and long cyclability, making them an ideal candidate for power sources in new-generation electronic devices. To boost their electrochemical performances, deriving activated carbon doped with heteroatoms such as N, O, and S are highly desirable for increasing the specific capacitance. In this regard, activated carbon (AC) self-doped with heteroatoms is directly derived from bio-waste (lima-bean shell) using different KOH activation processes. The heteroatom-enriched AC synthesized using a pretreated carbon-to-KOH ratio of 1:2 (ONS@AC-2) shows excellent surface morphology with a large surface area of 1508 m2 g-1 . As an SC electrode material, the presence of heteroatoms (N and S) reduces the interfacial charge-transfer resistance and increases the ion-accessible surface area, which inherently provides additional pseudocapacitance. The ONS@AC-2 electrode attains a maximum specific capacitance (Csp ) of 342 F g-1 at a specific current of 1 Ag-1 in 1 m NaClO4 electrolyte at the wide potential window of 1.8 V. Moreover, as symmetric SCs the ONS@AC-2 electrode delivers a maximum specific capacitance (Csc ) of 191 F g-1 with a maximum specific energy of 21.48 Wh kg-1 and high specific power of 14 000 W kg-1 and excellent retention of its initial capacitance (98 %) even after 10000 charge/discharge cycles. In addition, a flexible supercapacitor fabricated utilizing ONS@AC-2 electrodes and a LiCl/polyvinyl alcohol (PVA)-based polymer electrolyte shows a maximum Csc of 119 F g-1 with considerable specific energy and power.

10.
Food Chem ; 289: 299-307, 2019 Aug 15.
Article in English | MEDLINE | ID: mdl-30955616

ABSTRACT

Rice is a staple food in many countries around the world and it is a source of not only the nutrients, but also toxic elements. In this study, we evaluated four degrees of polishing and determined the elemental content (P, S, K, Mn, Fe, Ni, Cu, Zn, As, Se, Mo, Cd, Hg, Pb) in brown rice, rice bran and the resulting white rice using microwave assisted decomposition followed by inductively coupled plasma mass spectrometry (ICP-MS) detection. Additionally, individual rice grains at every polishing step were analyzed by laser ablation ICP-MS to generate elemental distribution maps. While P, K, Mn and Fe were predominantly located in bran layer, S, Cu, Zn, As, Se, Mo, Cd, and Hg were present in both the bran and endosperm. As the elemental distribution in the grain varies, polishing to produce white rice results in removal of different amounts of nutrient and toxic elements.


Subject(s)
Metals, Heavy/analysis , Nutrients/analysis , Oryza/chemistry , Dietary Fiber/analysis , Endosperm/chemistry , Endosperm/metabolism , Mass Spectrometry , Microwaves , Oryza/metabolism , Trace Elements/analysis
11.
J AOAC Int ; 102(4): 1194-1198, 2019 Jul 01.
Article in English | MEDLINE | ID: mdl-30709428

ABSTRACT

Background: The performance of U.S. Food and Drug Administration (FDA) Elemental Analysis Manual (EAM) 4.13 method (Inductively Coupled Plasma-Mass Spectrometric Determination of Iodine in Food Using Tetramethyl Ammonium Hydroxide Extraction) was tested in an interlaboratory study. Objective: The aim of the study is to demonstrate that the FDA EAM method 4.13 is applicable for the analysis of food and multivitamins. Methods: Six collaborators participated in the study using four different models of inductively coupled plasma-mass spectrometry instruments. The method evaluation included determination of the limits of detection and quantification, analysis of National Institute of Standards and Technology standard reference materials (SRMs), unknown samples, blinded SRMs, and fortified analytical portions by all six collaborators. The samples were chosen to represent all sectors of the AOAC food triangle and additionally included pet food and multivitamin tablets. Results: The repeatability and reproducibility ranges were 1.8-11.4% and 3.6-13.7%, respectively; the calculated HorRat values were in the 0.17-1.18 range; and 174 of 175 SRM analyses had z-scores <2 and fortified analytical portion samples with recoveries of 102-105%, indicating acceptable method performance. Conclusions: The study supports a Level Three Multilaboratory Validation according to FDA Food and Veterinary Program Guidelines performed by six collaborators using six certified reference materials and nine unknown samples. Highlights: The method is applicable for quantification of the total extractable iodine in food and multivitamin dietary supplements.


Subject(s)
Iodine/analysis , Quaternary Ammonium Compounds/chemistry , Dietary Supplements/analysis , Food Analysis/methods , Mass Spectrometry/methods , Reproducibility of Results , Solid Phase Extraction/methods , United States , United States Food and Drug Administration
12.
Biol Trace Elem Res ; 190(1): 45-51, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30293130

ABSTRACT

Environmental metal exposure, as well as dietary metals, may adversely affect semen quality even as others play an essential role in normal spermatogenesis and fertility. Measures of seminal fluid metals have therefore been of high interest in the last several decades but have shown inconsistent results in correlations with some semen quality parameters. As well, environmental metal measures across various body fluid matrices have not been consistently correlated contrary to what one might hypothesize based on a systemic body burden of metal. This may be due to the body fluid matrices assessed and to other differences in laboratory methods and sample preparation. Measures of uranium, a potentially toxic metal in humans, have not previously been reported in the semen of environmentally metal-exposed populations. We report here uranium seminal fluid results and the high correlation of uranium concentrations across several body fluid matrices in a cohort of military veterans exposed to depleted uranium in combat events during the Iraqi Gulf War. These results inform the risk communication conversation for exposed populations and broaden the public health assessments from various exposure scenarios.


Subject(s)
Semen/metabolism , Uranium/blood , Body Fluids/chemistry , Cohort Studies , Environmental Exposure/adverse effects , Gulf War , Humans , Male , Occupational Exposure/adverse effects , Semen Analysis/methods , Veterans
13.
Article in English | MEDLINE | ID: mdl-26730958

ABSTRACT

This work shows a method for the determination of iodine in a variety of food samples and reference materials using inductively coupled plasma-mass spectrometry (ICP-MS) following alkaline extraction. Optimisation of the addition of organic carbon showed that a minimum of 3% 2-propanol was necessary for a constant ratio of iodine to internal standard. The limit of quantification (LOQ), calculated as 30σ for the method, was 36 ng g(-1) in solid food samples. For method validation, seven standard reference materials (SRM) and 21 fortified food samples were used. The precision (%RSD) of the measurements was in the 2-7% range. Accuracies for the SRMs were 85-105%, while the fortified food samples showed 81-119% recoveries, including a number of samples fortified at 50% of the LOQ.


Subject(s)
Food Analysis/methods , Iodine/analysis , Mass Spectrometry
14.
Article in English | MEDLINE | ID: mdl-26515534

ABSTRACT

This paper reports the effects of rinsing rice and cooking it in variable amounts of water on total arsenic, inorganic arsenic, iron, cadmium, manganese, folate, thiamin and niacin in the cooked grain. We prepared multiple rice varietals both rinsed and unrinsed and with varying amounts of cooking water. Rinsing rice before cooking has a minimal effect on the arsenic (As) content of the cooked grain, but washes enriched iron, folate, thiamin and niacin from polished and parboiled rice. Cooking rice in excess water efficiently reduces the amount of As in the cooked grain. Excess water cooking reduces average inorganic As by 40% from long grain polished, 60% from parboiled and 50% from brown rice. Iron, folate, niacin and thiamin are reduced by 50-70% for enriched polished and parboiled rice, but significantly less so for brown rice, which is not enriched.


Subject(s)
Arsenic/analysis , Cooking , Food Contamination/analysis , Oryza/chemistry , Vitamins/analysis , Water/chemistry , Edible Grain/chemistry
15.
Article in English | MEDLINE | ID: mdl-26030688

ABSTRACT

We hypothesized that Tabun poisoning, as well as other organophosphorous treatment, cause specific organs' oxidative changes that have not previously been substantiated investigated. In this regard, a marker for nitrosative-oxidative stress in the main haemodynamic organs (heart and kidney) could reveal the existence of such changes. In this study, for the first time we studied the nitrosative/oxidative stress in heart and kidney after acute Tabun (Ethyl N,N- Dimethylphosphoramidocyanidate) poisoning measuring by immunohistochemistry the expression of 3-nitrotyrosine--a marker for nitrosative-oxidative stress. We investigated nitrotyrozine expression in three different groups of animals (with at least 3 animals in each group): the first group was treated with 0.5 LD50 Tabun and organs were collected after 24 h; the second group received vehicle for the same period; in the third group a highly specific re-activator was applied immediately after Tabun application. Heart and kidney were collected after 24 h. The levels of nitrotyrozine production significantly increased (more than 3 times) in cardiomyocytes after Tabun. The application of re-activator slightly reduced these levels not reaching the basal heart levels. Nitrotyrozine expression in kidney increased more than 2 times after Tabun and application of re-activator did not change it significantly. In conclusion, our study evidently demonstrated that Tabun trigger oxidative-nitrosative stress in heart and kidney and these cellular effects should be protected by an additional anti-oxidant therapy, since acetylcholinesterase re-activator is not efficient in this manner.


Subject(s)
Heart/drug effects , Kidney/drug effects , Kidney/metabolism , Myocardium/metabolism , Organophosphates/toxicity , Oxidation-Reduction/drug effects , Oxidative Stress/drug effects , Animals , Male , Nerve Agents/toxicity , Rats , Rats, Wistar , Tyrosine/analogs & derivatives
16.
Article in English | MEDLINE | ID: mdl-26005363

ABSTRACT

AIM: The aim of this study was to compare two nationwide cross-sectional studies of diabetes prevalence in Bulgaria (2006 and 2012) and to assess its dynamics. MATERIAL AND METHODS: The two studies included 2396 and 2033 subjects, respectively. The International Diabetes Federation (IDF) diagnostic criteria were applied, and the data were weighed for type of settlement and age. RESULTS: Diabetes prevalence was found to be 7.9% in 2006 and 9.55% in 2012, P = 0.06, showing an increase of 20.9%. The absolute increase was 0.9% in the females and 2.3% in the males (P < 0.09). The increase was the largest in those aged 50-59: [9.4%, 2006 vs. 15.7%, 2012, P < 0.01]. Diabetes prevalence increased in the 20-60-year olds by 6.8% and decreased in the elderly by 6.1%. Obesity increased from 26.7 to 32.7%, P < 0.02. CONCLUSIONS: A significant increase in diabetes prevalence was found that necessitates healthcare measures and resources for community-based awareness and prevention programs.

17.
Autoimmunity ; 47(3): 162-72, 2014 May.
Article in English | MEDLINE | ID: mdl-24502777

ABSTRACT

Self-specific B cells play a main role in the pathogenesis of lupus. This autoimmune disease is characterized by the generation of autoantibodies against self antigens, and the elimination of B and T cells involved in the pathological immune response is a logical approach for effective therapy. We have previously constructed a chimeric molecule by coupling a DNA-mimotope peptides to an anti-CD32 antibody. Using this protein molecule for the treatment of lupus-prone MRL/lpr mice, we suppressed selectively the autoreactive B-lymphocytes by cross-linking B cell receptors with the inhibitory FcγRIIb receptors. This approach was limited by the development of anti-chimeric antibodies in MRL mice. In order to avoid this problem, we established a murine severe combined immunodeficiency lupus model, allowing a long-term chimera therapy. Elimination of the double-stranded DNA-specific B cells by chimera therapy in MRL-transferred immunodeficient mice resulted in inhibition of T cell proliferation and prevented the appearance of IgG anti-DNA antibodies and of proteinuria.


Subject(s)
B-Lymphocytes/immunology , DNA/immunology , Lupus Erythematosus, Systemic/immunology , Adoptive Transfer , Animals , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/pharmacology , B-Lymphocytes/drug effects , Cell Proliferation/drug effects , DNA/chemistry , DNA/metabolism , Disease Models, Animal , Female , Humans , Immunoglobulins, Intravenous/administration & dosage , Kidney Glomerulus/immunology , Kidney Glomerulus/pathology , Lupus Erythematosus, Systemic/metabolism , Lupus Erythematosus, Systemic/mortality , Lupus Erythematosus, Systemic/pathology , Lupus Erythematosus, Systemic/therapy , Lymphocyte Activation/drug effects , Lymphocyte Activation/immunology , Male , Mice , Mice, Inbred MRL lpr , Mice, SCID , Peptides/chemistry , Peptides/immunology , Peptides/metabolism , Premedication , Receptors, IgG/metabolism , Signal Transduction , T-Lymphocytes/drug effects , T-Lymphocytes/immunology
18.
J Trace Elem Med Biol ; 27(1): 2-6, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22944582

ABSTRACT

In this study we report uranium analysis for human semen samples. Uranium quantification was performed by inductively coupled plasma mass spectrometry. No additives, such as chymotrypsin or bovine serum albumin, were used for semen liquefaction, as they showed significant uranium content. For method validation we spiked 2g aliquots of pooled control semen at three different levels of uranium: low at 5 pg/g, medium at 50 pg/g, and high at 1000 pg/g. The detection limit was determined to be 0.8 pg/g uranium in human semen. The data reproduced within 1.4-7% RSD and spike recoveries were 97-100%. The uranium level of the unspiked, pooled control semen was 2.9 pg/g of semen (n=10). In addition six semen samples from a cohort of Veterans exposed to depleted uranium (DU) in the 1991 Gulf War were analyzed with no knowledge of their exposure history. Uranium levels in the Veterans' semen samples ranged from undetectable (<0.8 pg/g) to 3350 pg/g. This wide concentration range for uranium in semen is consistent with known differences in current DU body burdens in these individuals, some of whom have retained embedded DU fragments.


Subject(s)
Mass Spectrometry/methods , Semen/chemistry , Uranium/analysis , Humans , Male
19.
Microchem J ; 105: 101-107, 2012 Nov 01.
Article in English | MEDLINE | ID: mdl-23175155

ABSTRACT

Arsenic (As) is a well documented human carcinogen. However, its mechanisms of toxic action and carcinogenic potential in animals have not been conclusive. In this research, we investigated the biochemical and genotoxic effects of As and studied its distribution in selected tissues of Sprague-Dawley rats. Four groups of six male rats, each weighing approximately 60 ± 2 g, were injected intraperitoneally, once a day for 5 days with doses of 5, 10, 15, 20 mg/kg bw of arsenic trioxide. A control group was also made of 6 animals injected with distilled water. Following anaesthetization, blood was collected and enzyme analysis was performed by spectrophotometry following standard protocols. At the end of experimentation, the animals were sacrificed, and the lung, liver, brain and kidney were collected 24 h after the fifth day treatment. Chromosome and micronuclei preparation was obtained from bone marrow cells. Arsenic exposure significantly increased (p<0.05) the activities of plasma alanine aminotransferase-glutamate pyruvate transaminase (ALT/GPT), and aspartate aminotransferase-glutamate oxaloacetate transaminase (AST/GOT), as well as the number of structural chromosomal aberrations (SCA) and frequency of micronuclei (MN) in the bone marrow cells. In contrast, the mitotic index in these cells was significantly reduced (p<0.05). These findings indicate that aminotransferases are candidate biomarkers for arsenic-induced hepatotoxicity. Our results also demonstrate that As has a strong genotoxic potential, as measured by the bone marrow SCA and MN tests in Sprague-Dawley rats. Total arsenic concentrations in tissues were measured by inductively coupled plasma mass spectrometry (ICP-MS). A dynamic reaction cell (DRC) with hydrogen gas was used to eliminate the ArCl interference at mass 75, in the measurement of total As. Total As doses in tissues tended to correlate with specific exposure levels.

20.
Eur J Immunol ; 41(11): 3301-11, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21830207

ABSTRACT

Although the exact etiology of systemic lupus erythematosus (SLE) remains elusive, B-cell hyperactivity and production of autoantibodies directed to components of the cell nucleus are a well-established pathogenetic mechanism of the disease. Therefore, the targeted inhibition of DNA-specific B cells is a logical therapeutic approach. The complement receptor type 1 (CR1, CD35) has been shown to suppress human B-cell activation and proliferation after co-cross-linking with the BCR, and may serve as a mediator for negative signal delivery. In order to evaluate this therapeutic approach in a human-like system, we used immune-restricted SCID mice transferred with PBMCs from SLE patients. The tolerance of these humanized SCID mice to native DNA was re-established after administration of a chimeric molecule consisting of a CR1-specific mAb coupled to the decapeptide DWEYSVWLSN that mimics dsDNA. The generated protein-engineered chimera was able to co-cross-link selectively native DNA-specific BCR with the B-cell inhibitory receptor CR1, thus delivering a strong inhibitory signal.


Subject(s)
Antibodies, Antinuclear/immunology , Antibodies, Monoclonal/immunology , B-Lymphocytes/immunology , Immunotherapy/methods , Lupus Erythematosus, Systemic/immunology , Animals , Antibodies, Antinuclear/biosynthesis , Antibodies, Antinuclear/therapeutic use , Antibodies, Monoclonal/biosynthesis , Antibodies, Monoclonal/therapeutic use , Autoantigens/immunology , Autoimmunity/immunology , Blotting, Western , Cell Line , Cell Separation , DNA/immunology , Disease Models, Animal , Flow Cytometry , Humans , Immunoprecipitation , Lymphocyte Activation/immunology , Mice , Mice, SCID , Peptides , Receptors, Complement 3b/immunology , Receptors, Complement 3b/therapeutic use , Signal Transduction/immunology
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