Assessing Chronic Heavy Metal Exposure by Analysis of Human Cataract Specimens and the Relationship to Metabolic Profiles.

Purpose: With age, the mammalian lens forms successive layers of crystallin protein fibers which infoliate with lens growth and development. As heavy metals generally bind to tissue protein, heavy metals are posited to sequester within the lens with age. Therefore, this study aims to compare heavy metals in human crystalline lens of older adults to known physiologic blood and urine levels and assess the association between concentrations in the lens and metabolic biomarkers.

Reports of Batch-Dependent Suspected Adverse Events of the BNT162b2 mRNA COVID-19 Vaccine: Comparison of Results from Denmark and Sweden.

: An unexpected batch-dependent safety signal for the BNT162b2 mRNA COVID-19 vaccine was recently identified in a nationwide study from Denmark, but the generalizability of this finding is unknown. Therefore, we compared batch-dependent rates of suspected adverse events (SAEs) reported to national authorities in Denmark and Sweden. : SAE and vaccine batch data were received from national authorities in Denmark and Sweden, and analyses of heterogeneity in the relationship between numbers of vaccine doses and SAEs per batch were performed, along with comparison of SAE rates and severities for batches that were shared between the two countries.

Development of a new accurate lateral flow immunoassay for diagnosis of human leptospirosis.

Purpose: The current diagnostic methods for leptospirosis diagnosis are technically complex and expensive, with limited applicability to specialized laboratories. Furthermore, they lack diagnostic accuracy in the acute stage of the disease, which coincides with a period when antibiotics are highly effective. New simple and accurate tests are mandatory to decentralize and improve diagnosis.

Utility evaluation of two molecular methods for spp. typing in human serum samples.

Most of the available genotyping methods were applied and evaluated in isolates and only few of them in a relevant sample size of blood specimens but not of sera. The objective of this study was to evaluate the utility of one partial 16S rRNA gene sequencing assay (16S rRNA) and an optimized. Multilocus sequence typing scheme (MLST) for typing directly in serum samples.

Development of an analytical method for determination of lead and cadmium in biological materials by GFAAS using Escherichia coli as model substance.

In this work, an analytical method was developed for the determination of lead and cadmium in biological samples using graphite furnace atomic absorption spectrometry. Escherichia coli (E. coli) was chosen as model substance for this purpose as it is readily available in most laboratories and can be quickly and easily prepared with a high turnaround rate.

Effect of cannabidiol oil on the color stability of resin composites.

Purpose: To evaluate the influence of cannabidiol (CBD) oil on the color stability of resin composites.

Methods: Three different resin composites were chosen to prepare 90 disk-shaped specimens. The specimens were randomly selected to compose two test groups (classic CBD or chocolate CBD) and one control group (distilled water) for a 14-day test.

Using mass spectrometry to overcome the longstanding inaccuracy of a commercially-available clinical testosterone immunoassay.

Accurate measurement of testosterone is important for the diagnosis of gonadal disorders in men, women, and children. Testosterone measurement has limited accuracy at low concentrations by most commercially available immunoassays. We aimed to develop an LC-MS/MS assay to address the inaccuracy of the in-house immunoassay observed over the past decade and to replace it with the new assay.

Presence of spp. in (Crocodylia, Alligatoridae) populations in Santa Fe, Argentina.

Leptospirosis is a disease caused by pathogenic spirochetes of the genus , transmitted by wild and domestic animals. Rodents play a fundamental role in the transmission cycle of this zoonosis but the function of reptiles is unknown. For example, crocodilians could play an important role in the transmission of this disease by living in ideal environments (bodies of shallow water and high temperatures) for the colonization of this bacterium.

Seroprevalence of leptospiral antibodies in rodents from riverside communities of Santa Fe, Argentina.

Background: Leptospirosis is a zoonotic disease that can be transmitted by contact with the urine of infected mammals. Rodents play a mayor role in the transmission of leptospires to humans. The province of Santa Fe reports the greatest number of cases in Argentina.

Calibrating from Within: Multipoint Internal Calibration of a Quantitative Mass Spectrometric Assay of Serum Methotrexate.

Background: Clinical LC-MS/MS assays traditionally require that samples be run in batches with calibration curves in each batch. This approach is inefficient and presents a barrier to random access analysis. We developed an alternative approach called multipoint internal calibration (MPIC) that eliminated the need for batch-mode analysis.

[First report on Leptospira interrogans in the sigmodontine rodent Scapteromys aquaticusPrimeiro relato da presença de Leptospira interrogans em roedores sigmodontíneos Scapteromys aquaticus].

Leptospirosis is a globally distributed zoonosis that can be transmitted through direct or indirect contact with the urine or tissues of infected animals. In Argentina, leptospirosis is endemic in the province of Santa Fe and epidemic outbreaks occur during floods. However, very little is known about the role that wild rodents play in the spread of the disease in Argentina.

Quantification of Methotrexate in Human Serum and Plasma by Liquid Chromatography Tandem Mass Spectrometry.

Mass spectrometry (MS) is a highly specific and sensitive technique that is used for the detection of many different analytes with diverse chemical characteristics. It has been adopted by clinical laboratories for the quantification of small molecules and, by extension, has been widely used for therapeutic drug monitoring. It is an attractive alternative to immunoassay methods, because it is not subject to the same interferences.

Diagnostic accuracy of an IgM enzyme-linked immunosorbent assay and comparison with 2 polymerase chain reactions for early diagnosis of human leptospirosis.

Enzyme-linked immunosorbent assay (ELISA) tests and polymerase chain reaction (PCR) may play a key role for early detection and treatment of human leptospirosis in developing countries. The aims of this study were to develop and validate an IgM ELISA under field conditions and to compare the diagnostic accuracy among IgG, IgM ELISAs, conventional PCR (cPCR), and real-time PCR (rtPCR) for early detection of human leptospirosis. Overall accuracy of IgM ELISA was sensitivity of 87.

Isolation and clinical sample typing of human leptospirosis cases in Argentina.

Leptospira typing is carried out using isolated strains. Because of difficulties in obtaining them, direct identification of infective Leptospira in clinical samples is a high priority. Multilocus sequence typing (MLST) proved highly discriminatory for seven pathogenic species of Leptospira, allowing isolate characterization and robust assignment to species, in addition to phylogenetic evidence for the relatedness between species.

[Evaluation of a reduced panel of leptospira strains for microagglutination].

Objective: To evaluate if the use of the 19 Leptospira strains panel suggested by the International Leptospirosis Society of World Health Organization for microagglutination allows confirmation of more cases that the 12 strains panel used in Argentina.

Materials And Methods: Cross-sectional observational study. We studied 441 serum samples corresponding to Argentinean patients with suspected leptospirosis derived during from July to December, 2009 and from January to October, 2013.

A comprehensive study of umbilical cord blood cell developmental changes and reference ranges by gestation, gender and mode of delivery.

Objective: The purpose of this study was to determine the normal hematological values in cord blood during gestation, the impact of the type of delivery and differences in gender.

Study Design: The database included 10 287 live births of 30-44 weeks gestation from cesarean or vaginal deliveries. Cord blood was collected into bags containing lyophilized heparin.

Color stability of shade guides after autoclave sterilization.

This study evaluated the influence of 120 autoclave sterilization cycles on the color stability of two commercial shade guides (Vita Classical and Vita System 3D-Master). The specimens were evaluated by spectrophotometer before and after the sterilization cycles. The color was described using the three-dimensional CIELab system.

Statistical analysis of aerosol species, trace gasses, and meteorology in Chicago.

Both canonical correlation analysis (CCA) and principal component analysis (PCA) were applied to atmospheric aerosol and trace gas concentrations and meteorological data collected in Chicago during the summer months of 2002, 2003, and 2004. Concentrations of ammonium, calcium, nitrate, sulfate, and oxalate particulate matter, as well as, meteorological parameters temperature, wind speed, wind direction, and humidity were subjected to CCA and PCA. Ozone and nitrogen oxide mixing ratios were also included in the data set.

Design and implementation of software for automated quality control and data analysis for a complex LC/MS/MS assay for urine opiates and metabolites.

Background: Mass spectrometry provides a powerful platform for performing quantitative, multiplexed assays in the clinical laboratory, but at the cost of increased complexity of analysis and quality assurance calculations compared to other methodologies.

Methods: Here we describe the design and implementation of a software application that performs quality control calculations for a complex, multiplexed, mass spectrometric analysis of opioids and opioid metabolites.

Results: The development and implementation of this application improved our data analysis and quality assurance processes in several ways.

[Human leptospirosis diagnosis:macroscopic agglutination test evaluation in different stages of the disease].

Objective: To evaluate the macroscopic agglutination test using Temperature Resistant (TR) antigen as a screening test for the diagnosis of human leptospirosis in different stages of the disease.

Materials And Methods: The criteria for case definition were based on the results of the microscopic agglutination test (MAT), leukocyte counts and neutrophilia, resulting 218 confirmed cases and 242 non- cases. Each sample was classified according to the days of the disease progression in three stages: first (<10 days), second (10 - 25 days) and third (> 25 days).

Opalescence of bleached teeth.

Objectives: To evaluate the influence of tooth bleaching on the opalescence properties of enamel.

Methods: Color of 38 specimens was determined by colorimetric analysis before and after bleaching in the reflectance and transmittance modes. The results were described as CIELab color coordinates.