209 research outputs found

    Advantages and risks of nanotechnologies in cancer patients and occupationally exposed workers.

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    Introduction: In recent years, different nanotechnology platforms for drug delivery in the area of medical biology have gained remarkable attention. Areas covered: Nanoparticles (NPs) used as drug delivery vehicles consist of different materials such as natural or synthetic polymers, lipids or metals. They have an ultra-small size, large surface area-to-mass ratio and high reactivity. Although there are many data on the advantages in terms of both higher efficacy and less adverse effects of nanodrugs, several recent findings have reported unexpected toxicities giving origin to nanotoxicology. Expert opinion: Despite the great promise that NPs show, few studies have examined the human body's reaction due to NP exposure in both patients and workers. To perform this type of evaluation, it is necessary to define an adequate index of exposure, and the measure of this index is representative of what the worker is breathing. The properties of the nanomaterials used for designing NPs, such as in the case of poorly biocompatible materials (carbon nanotubes or heavy metals), and their chemical composition (as in the case of liposomes) largely contribute in determining potential side effects. Awareness of the levels of particles, which can cause health effects, is necessary for the workers and exposed patients

    Molecular profile of sensitization in subjects with short occupational exposure to latex

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    Objectives: We examined the prevalence of latex allergy in subjects with occupational exposure to latex allergens for less than 5 years, determining the disease spectrum in symptomatic workers. We identified the most frequent molecular allergens by Immuno- CAP (ICAP), correlating the findings with skin prick test (SPT) results. Material and Methods: Seven hundred twenty-three healthcare students using latex gloves on a regular basis were invited to participate in a baseline questionnaire screening. An ICAP serum test was performed only when a possible latex allergy was indicated by the questionnaire. Results: The total number of participants responding to the baseline survey was 619. Glove-related symptoms were indicated by 4% (N = 25) of the students. The most common symptom was contact dermatitis (N = 18, 72%). In 12 subjects, ICAP revealed a real sensitization to latex, with a recombinant latex allergen profile showing a high frequency for rHev b 6.01 specific immunoglobulin E (sIgE) (N = 9, 67%). In these individuals, skin symptoms were more prevalent than other types (88%). Conclusions: The combined positivity for rHev b 6.01, rHev 8 and rHev b 5 determined by ICAP identified 92% of latex-allergic subjects with short-term exposure to latex

    Characterization of a bacteriocin produced by a clinical isolate of Shigella flexneri 2

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    This study was conducted to determine the emergence of antibiotic resistant/producer strains, focusing the efforts in the search for new antimicrobial compounds. A total of 15,131 fecal samples (CI) were analyzed from patients from acute diarrhea (2015-2017 period) and observed that 1,794 were positive for either E. coli, Shigella or Salmonella presence. The ability of 388 Shigella isolates to produce antimicrobial peptides was determined by deferred-antagonism assay. Here, we observed that 9.02% of the Shigella isolates produced an antimicrobial agent able to inhibit the E. coli AB133 strain growth. The CI172 strain was selected as producer for its antimicrobial characterization. This antagonist compound (ShpCI172) was produced during exponential growth phase and displayed a restricted action spectrum. It is also thermo-resistant and has about 3 kDa molecular mass. The ShpCI172 can be classified as a microcin, since CI172 did not display cross immunity with other well-known microcins. This is the first report where the production of a microcin by a Shigella flexneri 2 strains is described. The use of ShpCI172 microcin may contribute to preventing or controlling diarrheal diseases. This finding represents an important contribution in the biotechnology field for its application in the development of new antibiotics and/or food preservatives agents.Fil: Torrez Lamberti, Monica Florencia. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - TucumĂĄn. Instituto Superior de Investigaciones BiolĂłgicas. Universidad Nacional de TucumĂĄn. Instituto Superior de Investigaciones BiolĂłgicas; ArgentinaFil: Lopez, Fabian Enrique. Universidad Nacional de Chilecito; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - TucumĂĄn. Instituto Superior de Investigaciones BiolĂłgicas. Universidad Nacional de TucumĂĄn. Instituto Superior de Investigaciones BiolĂłgicas; ArgentinaFil: Bianchi, A. M.. Hospital del Niño JesĂșs; ArgentinaFil: Pescaretti, MarĂ­a de Las Mercedes. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - TucumĂĄn. Instituto Superior de Investigaciones BiolĂłgicas. Universidad Nacional de TucumĂĄn. Instituto Superior de Investigaciones BiolĂłgicas; ArgentinaFil: Delgado, Monica Alejandra. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - TucumĂĄn. Instituto Superior de Investigaciones BiolĂłgicas. Universidad Nacional de TucumĂĄn. Instituto Superior de Investigaciones BiolĂłgicas; Argentin

    Crown-Ether Functionalized Graphene Oxide Membrane for Lithium Recovery from Water

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    The massive worldwide transition of the transport sector to electric vehicles has dramatically increased the demand for lithium. Lithium recovery by means of ion sieves or supramolecular chemistry has been extensively studied in recent years as a viable alternative approach to the most common extraction processes. Graphene oxide (GO) has also already been proven to be an excellent candidate for water treatment and other membrane related applications. Herein, a nanocomposite 12-crown-4-ether functionalized GO membrane for lithium recovery by means of pressure filtration is proposed. GO flakes were via carbodiimide esterification, then a polymeric binder was added to improve the mechanical properties. The membrane was then obtained and tested on a polymeric support in a dead-end pressure setup under nitrogen gas to speed up the lithium recovery. Morphological and physico-chemical characterizations were carried out using pristine GO and functionalized GO membranes for comparison with the nanocomposite. The lithium selectivity was proven by both the conductance and ICP mass measurements on different sets of feed and stripping solutions filtrated (LiCl/HCl and other chloride salts/HCl). The membrane proposed showed promising properties in low concentrated solutions (7 mg(Li)/L) with an average lithium uptake of 5 mg(Li)/g in under half an hour of filtration time

    A mechanistic study on the cardiotoxicity of 5-fluorouracil in vitro and clinical and occupational perspectives

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    AbstractFluoropyrimidines are key agents for the treatment of gastrointestinal tract adenocarcinomas. The possible cardiotoxic effects in patients and occupationally exposed workers are multifactorial and remain a puzzle to solve for investigators. In the present study, we study what cell death pathways and what doses can determine direct cardiotoxic effects of 5-fluorouracil (5-FU) and doxorubicin (DOXO) on rat cardiocytes (H9c2) and a human colon adenocarcinoma (HT-29) cell line, already reported to be sensitive to 5-FU. We have found that 5-FU induced 50% growth inhibition (IC:50) at 72h with concentrations of 400ÎŒM and 4ÎŒM on H9c2 and HT-29, respectively. Moreover, we have found that the addition of Levofolinic Acid (LF) to 5-FU potentiated the growth inhibition induced by 5-FU. The growth inhibition induced by 5-FU alone or in combination with LF in cardiocytes was paralleled by an increase of thiobarbituric acid-reactive species (Tbars) and end products of nitric oxide (NO) suggesting the increase of the oxidative stress status in cardiocytes. Interestingly, these effects were strongly potentiated by the addition of LF, a biochemical modulator of 5-FU activity.Our data suggest that agents such as 5-FU different from anthracyclines, conventionally related to the induction of cardiotoxic effects, can also induce cardiocyte damage paralleled by oxidative stress. The strategies based upon the use of scavengers could be used in order to prevent this effect

    Solid-phase microextraction-gas chromatography-mass spectrometry method validation for the determination of endogenous substances: urinary hexanal and heptanal as lung tumor biomarkers

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    Hexanal and heptanal are endogenous aldehydes coming from membrane lipid oxidation, found in lung cancer patients’ blood, and suggested as lung tumor biomarkers. Here the urinary matrix was investigated instead of blood and the difficulties related to the determination of endogenous substances in biological matrices were faced by developing an external calibration HS-SPME/GC/MS method. The methodology was validated according to international validation procedures and it was verified analyzing unknown biological samples from cancer patients and healthy subjects. Percentage accuracy and precision, ranging from −11.25 to 10.85% and from 0.45 to 4.46%, respectively, were obtained, together with limits of detection (LODs) and lower limits of quantification (LLOQs) of 0.11 and 0.23 pg L−1 for hexanal and of 0.10 and 0.21 pg L−1 for heptanal. Analytes percentage recoveries (66.3%, hexanal and 70.5%, heptanal) and stability were evaluated. No analytes degradation was found at room temperature, while the remarkable analytes loss found after 1 month storage suggests analyzing biological samples within a week from storage. Results coming from the analysis of unknown biological samples showed no evident differences of heptanal urinary excretion between lung cancer patients and healthy subjects (0.22–0.95 and 0.21–0.69 pg L−1, respectively), while hexanal urinary concentrations in cancer patients (0.24–4.36 pg L−1) were slightly higher than those found in control group ones (0.23–1.26 pg L−1). The obtained results highly suggest to do further investigations in order to collect statistically significant biological data to discriminate between the pathological state of lung cancer patients and physiological conditions of healthy subjects, using the simple, rapid and cheap method here reported for the quantification of urinary aldehydes

    Surface bioengineering of diatomite based nanovectors for efficient intracellular uptake and drug delivery

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    Diatomite is a natural porous silica material of sedimentary origin. Due to its peculiar properties, it can be considered as a valid surrogate of synthetic porous silica for nano-based drug delivery. In this work, we exploit the potential of diatomite nanoparticles (DNPs) for drug delivery with the aim of developing a successful dual-biofunctionalization method by polyethylene glycol (PEG) coverage and cell-penetrating peptide (CPP) bioconjugation, to improve the physicochemical and biological properties of the particles, to enhance the intracellular uptake in cancer cells, and to increase the biocompatibility of 3-aminopropyltriethoxysilane (APT) modified-DNPs. DNPs-APT-PEG-CPP showed hemocompatibility for up to 200 mu g mL(-1) after 48 h of incubation with erythrocytes, with a hemolysis value of only 1.3%. The cytotoxicity of the modified-DNPs with a concentration up to 200 mu g mL(-1) and incubation with MCF-7 and MDA-MB-231 breast cancer cells for 24 h, demonstrated that PEGylation and CPP-bioconjugation can strongly reduce the cytotoxicity of DNPs-APT. The cellular uptake of the modified-DNPs was also evaluated using the above mentioned cancer cell lines, showing that the CPP-bioconjugation can considerably increase the DNP cellular uptake. Moreover, the dual surface modification of DNPs improved both the loading of a poorly water-soluble anticancer drug, sorafenib, with a loading degree up to 22 wt%, and also enhanced the drug release profiles in aqueous solutions. Overall, this work demonstrates that the biofunctionalization of DNPs is a promising platform for drug delivery applications in cancer therapy as a result of its enhanced stability, biocompatibility, cellular uptake, and drug release profiles.Peer reviewe

    Molecular targets and oxidative stress biomarkers in hepatocellular carcinoma: an overview

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    Hepatocellular carcinoma (HCC) is a complex and heterogeneous tumor with multiple genetic aberrations. Several molecular pathways involved in the regulation of proliferation and cell death are implicated in the hepatocarcinogenesis. The major etiological factors for HCC are both hepatitis B virus (HBV) and hepatitis C virus infection (HCV)
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