Purpose: The objective of this study was to determine the normative vestibulo-ocular reflex gain output values of the computerized rotational head impulse test (crHIT) with stationary visual targets (earth bound) in healthy participants in each decade age band of life: 10-19, 20-29, 30-39, 40-49, 50-59, 60-69, and 70+ years.
Method: Seventy-seven community-dwelling participants (10-85 years of age) with normal lateral semicircular canal (SCC) functioning and no symptoms or history of vestibular dysfunction were recruited through convenience sampling and assessed with the crHIT using stationary targets. These participants were assessed using two standard protocols in a randomized order.
Environmental surveillance of water sources is important to monitoring viral hepatitis transmission in clinical settings. This study investigated the circulation of hepatitis A (HAV) and E (HEV) viruses in sewage and clinical samples from Argentina. Between 2016 and 2017, 80 raw sewage samples and 86 clinical samples (stool and serum) from suspected cases of hepatitis A and hepatitis E were obtained.
View Article and Find Full Text PDFThe goal was to compare the micronucleus (MN) and dicentric plus ring chromosomes (D + R) assays for dose assessment in cases of partial body irradiations (PBI). We constructed calibration curves for each assay at doses ranging from 0 to 5 Gy of X-rays at dose rate of 0.275 Gy/min.
View Article and Find Full Text PDFBackground: Single-dose hepatitis A virus (HAV) vaccination was implemented in all Argentinean children 12 months of age in 2005. Previous studies demonstrated high prevalence of protective antibody response 4 years after single-dose vaccination. This study assessed long-term seroprotection against HAV after vaccination.
View Article and Find Full Text PDFThe possibility to reduce the culture time and volume of blood and reagents required for the chemical Premature Chromosome Condensation (PCC) assay is demonstrated in this work. Peripheral whole blood was exposed to gamma radiation (1-20 Gy). Lymphocytes were cultured for 40 h, using 50 μl of blood and 450 μl of culture medium.
View Article and Find Full Text PDFMitotic Index (MI) estimation expressed as percentage of mitosis plays an important role as quality control endpoint. To this end, MI is applied to check the lot of media and reagents to be used throughout the assay and also to check cellular viability after blood sample shipping, indicating satisfactory/unsatisfactory conditions for the progression of cell culture. The objective of this paper was to apply the CellProfiler open-source software for automatic detection of mitotic and nuclei figures from digitized images of cultured human lymphocytes for MI assessment, and to compare its performance to that performed through semi-automatic and visual detection.
View Article and Find Full Text PDFRecommendations for Hepatitis C screening based on risk factorsfor transmission proved to be ineffcient. Accordingly, the CDC recommended to screen all American individuals born between 1945-1965, based on data from population prevalence of infection. The effectiveness of implementing these recommendations in other contexts and/or populations can be estimated, in principle, knowing the age distribution of infected individuals.
View Article and Find Full Text PDFIntroduction: Hepatitis E is a disease of global distribution, with significant morbidity and mortality, whose scope and burden continue to emerge in low endemic countries.
Material And Methods: In 2012, we studied the prevalence of anti-HEV antibodies in 202 adult serum samples. We also analyzed samples from 143 patients with acute non-A-C hepatitis from January 2011 to December 2013.
The fast assessment of the dose received by exposed persons is crucial in radiological accidents, so the 48 h of cell culture in conventional cytogenetic dosimetry in addition to some limitations after high doses becomes a disadvantage. The premature chromosome condensation (PCC) assay permits to analyse enough cells after high radiation exposure, and the score of PCC-R may reduce the culture time up to 40-42 h. Peripheral whole-blood samples were exposed to 1-10 Gy of gamma radiation and cultured during 40 and 42 h.
View Article and Find Full Text PDFBackground: Unilateral centrifugation (UC) is a test of utricular function that involves the eccentric displacement of a patient while undergoing high velocity rotation. These off-center placements permit evaluation of utricles as only one organ is subjected to linear stimulation. Currently, several different protocols are used for translation times between positions (e.
View Article and Find Full Text PDFThe combination of automatic image acquisition and automatic image analysis of premature chromosome condensation (PCC) spreads was tested as a rapid biodosimeter protocol. Human peripheral lymphocytes were irradiated with (60)Co gamma rays in a single dose of between 1 and 20 Gy, stimulated with phytohaemaglutinin and incubated for 48 h, division blocked with Colcemid, and PCC-induced by Calyculin A. Images of chromosome spreads were captured and analysed automatically by combining the Metafer 4 and CellProfiler platforms.
View Article and Find Full Text PDFBy using molecular surveillance of hepatitis A virus, we characterized for the first time a subgenotype IB imported case in Argentina, a country with universal vaccination since 2005. The case was a crew member of a cruise ship. We consider this a case alert because of its multiple implications.
View Article and Find Full Text PDFBackground: Hepatitis E virus (HEV) has been described as an emerging pathogen in Brazil and seems to be widely disseminated among swine herds. An autochthonous human case of acute hepatitis E was recently reported. To obtain a better understanding of the phenotypic profiles of both human and swine HEV strains, a experimental study was conducted using the animal model, Macaca fascicularis.
View Article and Find Full Text PDFActa Gastroenterol Latinoam
June 2013
Two cases of hepatitis E that were assisted in our Unit of Hepatology and Liver Transplantation are described in this article. The first patient had prior hepatic involvement and therefore a more severe course, whereas the second case, with normal liver function, only developed a self-limited acute hepatitis.
View Article and Find Full Text PDFSeveral studies have demonstrated that viral load is a key factor to determine the development of HBV infection and to assess treatment options for the disease. There is a lack of studies analyzing viral load levels in chronic hepatitis B patients in Argentina and the epidemiologic information is limited. The aim of this study was to determine viral load levels and its distribution in patients diagnosed with chronic hepatitis B from geographical areas with high prevalence for HBV in Argentina.
View Article and Find Full Text PDFThe estimation of the dose and the irradiated fraction of the body is important information in the primary medical response in case of a radiological accident. The PCC-R assay has been developed for high-dose estimations, but little attention has been given to its applicability for partial-body irradiations. In the present work we estimated the doses and the percentage of the irradiated fraction in simulated partial-body radiation exposures at high doses using the PCC-R assay.
View Article and Find Full Text PDFISRN Pharmacol
December 2012
Immunocompetent mice, Fc receptor γ-chain deficient mice (Fcer1g(-/-)), and molecular tools as F(ab')(2) bivalent fragments appear as the most suitable biological models to study the mechanisms of the action of anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs). In vivo experiments contrasting antitumor effects of whole Abs and their bivalent fragments commonly involve a previous comparative pharmacokinetics study. In this paper, pharmacokinetics and biodistribution of an anti-mouse EGFR Ab were assessed using immunocompetent mice.
View Article and Find Full Text PDFObjective: To test a CellProfiler pipeline for automated counting and characterization of gamma-H2AX foci in color images of human cultured cells.
Study Design: A431 cells were irradiated and stained for gamma-H2AX foci detection. Sets of color images were analyzed visually, and findings were compared with those using FociCounter and CellProfiler software.
Epidermal growth factor receptors (EGFR) are overexpressed in a wide range of malignancies including head and neck, colon, and breast cancers. It has been identified that carcinomas with high expression levels of EGFR are more resistant to radiotherapy. Therefore, inhibiting nuclear translocation of EGFR to increase the radiosensitivity of malignant cells expressing EGFR offers the potential for increasing the therapeutic index of radiotherapy.
View Article and Find Full Text PDFCalibration curves for fission spectrum neutrons and other high LET radiations are scarce in cytogenetic dosimetry and particularly for Prematurely Condensed Chromosome Rings (PCC-ring). Here we analyzed the behavior of the PCC-ring frequency and PCC index after neutron irradiation in a broad dose interval from 1 to 26 Gy. PCC-rings were induced in lymphocytes with Calyculin A.
View Article and Find Full Text PDFBackground: In recent years, an increasing number of infections with genotype 3 hepatitis E virus (HEV) have been reported in western countries. Data in South America, however, are still scarce. Swine and human variants previously described in Argentina are closely related to a human Austrian one.
View Article and Find Full Text PDF1E10 is a murine anti-idiotypic mAb specific for an idiotypic mAb that reacts with NeuGc-containing gangliosides, sulfatides, and Ags expressed in some human tumors. In melanoma, breast, and lung cancer patients, this anti-idiotypic Ab was able to induce a specific Ab response against N-glycosylated gangliosides, attractive targets for cancer immunotherapy as these glycolipids are not naturally expressed in humans. A clinical study with nonsmall cell lung cancer patients showed encouraging clinical benefits.
View Article and Find Full Text PDFOne of the difficulties in the comparison of results between laboratories working with the comet assay is the great diversity of parameters used to express DNA damage and the lack of conversion factors between the majority of them. Here we report a scorer-independent conversion curve to transform the values of DNA damage reported in arbitrary units (AU) into estimated percentage of DNA in the tail (E%T), and the results obtained in an intercomparison exercise where the effectiveness of this curve and two others proposed in the literature (E%T=AU/4 and E%T=(AU/5)+10) were tested. To obtain the conversion curve, human lymphocytes were first treated with radiation or H(2)O(2).
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