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Zinc oxide nanoparticles (ZnO-NPs) have antimicrobial and a number of other properties, rendering apt their use in biomedicine, environmental remediation, agriculture, and other fields. Given the potential use of these nanoparticles (NPs) in these areas, it is necessary to determine their toxic effects on biological systems. This work therefore analyzed the histological changes in the respiratory nasal epithelium of Mus musculus biomodels exposed to atmospheres containing ZnO-NPs at different concentrations (6, 15, and 40 mg/m3). The NPs were synthesized using the Pechini polymeric complex method and characterized using techniques such as IR and Raman spectroscopies, X-ray diffraction (XRD), transmission (TEM), and scanning electron microscopy (SEM). The ZnO-NPs obtained had a wurtzite-type structure, with spheroidal morphology and a particle size of ~ 50 nm, and the Raman spectrum showed the presence of defects in its structure. The results of the treatments to which the biomodels were subjected showed that the inhalation of ZnO-NPs caused significant morphological changes in their nasal epithelium (squamous metaplasia and vascular congestion) and an acute inflammatory response when exposed to high concentrations of NPs (40 and 15 mg/m3). [ABSTRACT FROM AUTHOR]

Autoimmune (AI) diseases can affect many organs; however, the prostate has not been considered to be a primary target of these systemic inflammatory processes. Here, we utilize medical record data, patient samples, and in vivo models to evaluate the impact of inflammation, as seen in AI diseases, on prostate tissue. Human and mouse tissues are used to examine whether systemic targeting of inflammation limits prostatic inflammation and hyperplasia. Evaluation of 112,152 medical records indicates that benign prostatic hyperplasia (BPH) prevalence is significantly higher among patients with AI diseases. Furthermore, treating these patients with tumor necrosis factor (TNF)-antagonists significantly decreases BPH incidence. Single-cell RNA-seq and in vitro assays suggest that macrophage-derived TNF stimulates BPH-derived fibroblast proliferation. TNF blockade significantly reduces epithelial hyperplasia, NFκB activation, and macrophage-mediated inflammation within prostate tissues. Together, these studies show that patients with AI diseases have a heightened susceptibility to BPH and that reducing inflammation with a therapeutic agent can suppress BPH. Reduction of systemic autoimmunity using TNF blockers may also reduce inflammatory diseases in other organs. Here, the authors use a patient database and scRNA-seq to link autoimmune diseases to benign prostatic hyperplasia (BPH), and demonstrate that prostatic hyperplasia is reduced by TNF blockers in humans and mice. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles (ZnO-NPs) of different sizes and morphology were synthesized. The variables analyzed were zinc precursor concentration, the nature of the synthesis solvent and the concentration of surfactant agent. The solids synthesized were characterized using IR spectroscopy, X-ray diffraction (XRD) and transmission electron microscopy (TEM). Considering the nature of the synthesis process, a tentative model of the mechanism of formation of the ZnO-NPs was proposed. ZnO-NPs with spheroidal morphology were obtained with a 10 mM CTAB concentration and these were selected to study their toxicity. For this study, Mus musculus mice were therefore given an oral dose of 50 mg ZnO/kg body weight (b.v.). Biopsies obtained from the livers and kidneys of the mice studied were analyzed using TEM and atomic absorption. The biopsy of the liver of the mouse given a dose of ZnO-NPs showed evidence of steatosis. The atomic absorption results showed the accumulation of Zn in both the liver and the kidney of the mouse. [ABSTRACT FROM AUTHOR]

Radio spectrometers of the CALLISTO type to observe solar flares have been distributed to nine locations around the globe. The instruments observe automatically, their data is collected every day via internet and stored in a central data base. A public web-interface exists through which data can be browsed and retrieved. The nine instruments form a network called e-CALLISTO. It is still growing in the number of stations, as redundancy is desirable for full 24 h coverage of the solar radio emission in the meter and low decimeter band. The e-CALLISTO system has already proven to be a valuable new tool for monitoring solar activity and for space weather research. [ABSTRACT FROM AUTHOR]

Severe infections caused by Stenotrophomonas maltophilia are associated with high mortality, and strategies to improve the clinical outcome for infected patients are needed. A retrospective cohort study of patients with bloodstream infection (BSIs) and pneumonia caused by S. maltophilia was conducted. Multivariate analysis was performed to access factors associated with 14-day mortality. A total of 60 infections were identified. Among these, eight (13%) were pneumonias and 52 were BSIs; 33.3% were primary, 13% were central venous catheter (CVC)-related and 40% were secondary BSIs. Fifty-seven (85%) patients had received previous antimicrobial therapy; 88% had CVC, 57% mechanical ventilation and 75% were in the intensive care unit at the onset of infection. Malignancy (45%) was the most frequent underlying disease. The mean of the Acute Physiology and Chronic Health Evaluation II (APACHE II) scores was 17 and for the Sepsis-related Organ Failure Assessment (SOFA) score, it was 7 points. The overall and 14-day mortality were, respectively, 75% and 48%. Forty-seven (78%) patients were treated and, of these, 74% received trimethoprim-sulfamethoxazole. Independent risk factors associated with mortality were SOFA index >6 points (0.005) and septic shock (0.03). The Kaplan-Meier estimations curves showed that patients with APACHE II score >20 and SOFA score >10 had a survival chance of, respectively, less than 8% and less than 10% ( P≤0.001) at 21 days after the first positive S. maltophilia culture. Our results suggest that the independent factors associated with outcome in patients with infection caused by S. maltophilia are septic shock and higher SOFA index. [ABSTRACT FROM AUTHOR]

Stenotrophomonas maltophilia has emerged as an important nosocomial pathogen capable of causing respiratory, bloodstream, and urinary infections. The treatment of nosocomial infections by S. maltophilia is difficult, as this pathogen shows high levels of intrinsic or acquired resistance to different antimicrobial agents, drastically reducing the antibiotic options available for treatment. Intrinsic resistance may be due to reduced outer membrane permeability or to the multidrug efflux pumps. However, specific mechanisms of resistance such as aminoglycoside-modifying enzymes or the heterogeneous production of metallo-β-lactamase have contributed to the multidrug-resistant phenotype displayed by this pathogen. Moreover, the lack of standardized susceptibility tests and their interpretative criteria hinder the choice of an adequate antibiotic treatment. Recommendations for the treatment of infections by S. maltophilia are based on in vitro studies, certain nonrandomized clinical trials, and anecdotal experience. Trimethoprim-sulfamethoxazole remains the drug of choice, although in vitro studies indicate that ticarcillin-clavulanic acid, minocycline, some of the new fluoroquinolones, and tigecycline may be useful agents. This review describes the main resistance mechanisms, the in vitro susceptibility profile, and treatment options for S. maltophilia infections. [ABSTRACT FROM AUTHOR]

Investigates the genetic diversity among populations of the shrimp Farfantepenaeus notialis in Cuba. Pattern of allozyme variation; Mitochondrial DNA polymorphism; Genotypes of mitochondrial DNA found in the Ana Maria Gulf, Guacanayabo Gulf and Batabano Gulf; Two factors that may model genetic variation found at Ana Maria Gulf.

The objective of the study was to determine the shearing stress exerted by the suture thread under conditions of normal working stress. Thirty-six samples of calf pericardium, similar to that employed in the manufacture of bioprosthetic cardiac valve leaflets, were subjected to tensile testing. Prior to the trial, a continuous suture was sewn in the central zone of each sample, at a 45° angle to the longest axis of the sample, using commercially-available threads (silk, Gore-Tex, Surgilene and nylon). Application of the Mohr circle for combined wear revealed that the shearing stress ranged between 2.68-fold greater (for samples sewn with silk) and 5.48-fold greater (for samples sewn with nylon) than the working tensile stress in the region of the suture. It is concluded that the shearing stress is responsible for the limited durability of sutured samples of calf pericardium prepared to simulate bioprosthetic cardiac valve leaflets. © 1998 Chapman & Hall [ABSTRACT FROM AUTHOR]