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1.
Cureus ; 14(10): e29929, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36348880

RESUMO

Post the coronavirus disease 2019 (COVID-19) pandemic, there arises the concern of a new epidemic as cases of monkeypox are being confirmed, globally. With the initial clinical manifestation of monkeypox resembling that of the common cold or seasonal flu, recognizing alternative differential diagnoses is imperative as a medical health practitioner. The characteristic monkeypox maculopapular rash with the progression to vesicles and pustules before scabbing can be described in several other infections. Understanding the disease progression and distinct clinical presentation of monkeypox in its various stages may allow for a more expedient diagnosis among healthcare providers. Though eradicated, the clinical presentation of smallpox is the most similar to that of monkeypox; however, smallpox is no longer a concern for the general population. Other conditions such as molluscum contagiosum, syphilis, varicella zoster, measles, rickettsialpox, and scabies can present with rashes that may resemble singular or multiple states of the monkeypox rash progression. The ability to correctly diagnose an individual's condition promptly may allow healthcare providers to provide correct supportive therapies or treatments.

2.
Crit Care Explor ; 4(9): e0762, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36119397

RESUMO

COVID-19 can cause serious illness requiring multimodal treatment and is associated with secondary infections. Studies have suggested an increased risk of fungal infections, including candidemia following severe COVID-19 though understanding of risk factors and clinical outcomes remains unclear. OBJECTIVES: To describe clinical characteristics, outcomes and risk factors of candidemia among patients hospitalized with severe COVID-19. DESIGN SETTING AND PARTICIPANTS: A multicenter, case-control study of patients with severe COVID-19 was conducted to evaluate risk factors and clinical outcomes in patients who developed candidemia between August 2020 and August 2021. MAIN OUTCOMES AND MEASURES: Chart review evaluating institutional and patient demographics, clinical and mycological characteristics, concomitant interventions (antibiotics, immunosuppressive agents, parenteral nutrition, degree of oxygen support, mechanical ventilation, surgery), treatment regimens, and outcomes (length of stay and discharge disposition). RESULTS: A total of 275 patients were enrolled in the study, including 91 patients with severe COVID-19 and subsequent candidemia and 184 with severe COVID-19 without candidemia. Most patients received antibiotics prior to candidemia episode (93%), while approximately one-quarter of patients received biologic for COVID-19. In-hospital mortality was significantly higher in the cases compared with the controls (68% vs 40%; p < 0.01). Candida albicans was the most common (53%), followed by C. glabrata (19%). Use of central lines, biologic, and paralytics were independent risk factors for candidemia. CONCLUSIONS AND RELEVANCE: Candidemia following COVID-19 infection is a concern that requires clinical consideration and patient monitoring. Risk factors for the development of candidemia in the setting of COVID-19 infection are largely consistent with traditional risk factors for candidemia in hospitalized patients.

3.
J Agric Food Chem ; 67(45): 12393-12401, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31596571

RESUMO

Accumulation of toxic copper in soil and development of copper-resistant pests are emerging challenges currently faced by the agricultural community worldwide. As an alternative, we have developed a ternary zinc chelate solution (TSOL) pesticide where zinc ions are the primary active ingredient. The material is composed of zinc, urea, and hydrogen peroxide. Urea was chosen as it is widely used as a plant fertilizer and can also bind to both zinc and hydrogen peroxide. No phytotoxicity was observed with TSOL on Meyer lemon (Citrus × meyeri) seedlings at a field spray rate of 800 µg/mL Zn metal concentration. Antimicrobial studies showed that TSOL exhibited improved killing efficacy against Escherichia coli and Xanthomonas alfalfae compared to Zn ions alone. Citrus canker field trials in a grapefruit (Chrysopelea paradisi) grove over three years showed that TSOL provided comparable disease protection to copper products at an equivalent or lower metal content.


Assuntos
Antibacterianos/química , Citrus/microbiologia , Peróxido de Hidrogênio/química , Doenças das Plantas/microbiologia , Ureia/química , Zinco/química , Zinco/farmacologia , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Peróxido de Hidrogênio/farmacologia , Folhas de Planta/microbiologia , Ureia/farmacologia , Xanthomonas/efeitos dos fármacos , Xanthomonas/crescimento & desenvolvimento
4.
Glob Chall ; 3(7): 1800100, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31565385

RESUMO

This study addresses the mechanical response of nanoporous Si-Mg films, which are fabricated using free-corrosion dealloying and which represent an intriguing form of silicon that may find use as an anode material in lithium-ion batteries. The porous thin-film samples, in both the as-dealloyed and annealed states, are designed to have a final thickness of ≈1 µm so that substrate effects can be avoided during mechanical characterization in both the time and frequency domains. The as-dealloyed and annealed samples are investigated using a modified continuous stiffness measurement (CSM) technique that optimizes the ability to achieve steady-state harmonic motion, such that accurate phase angle measurements can be obtained; the as-dealloyed and annealed samples exhibit distinct phase angles of 1.9° and 2.6°, respectively. Observations made in the time domain suggest that the time dependence of nanoporous Si-Mg stems largely from plasticity. The reduced modulus values of as-dealloyed and annealed samples are investigated using the CSM technique and have corresponding values of 5.78 and 11.9 GPa, respectively. Similarly, the hardness of as-dealloyed and annealed samples are 167 and 250 MPa, respectively.

5.
Pathogens ; 8(3)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31374947

RESUMO

Nosocomial infections pose serious health concerns with over 2 million reported annually in the United States. Many of these infections are associated with bacterial resistance to antibiotics and hence, alternative treatments are critically needed. The objective of this study was to assess the antimicrobial efficacy of a gallium (Ga)-based particle coated with N-Acetyl Cysteine (Ga-NAC) against Pseudomonas aeruginosa PAO1. Our studies showed the Minimum Inhibitory Concentration (MIC) of PAO1 treated with Ga-NAC was 1 µg/mL. Cytotoxicity of Ga-NAC against multiple cell lines was determined with no cytotoxicity observed up to concentrations of 2000 µg/mL (metal concentration), indicating a high therapeutic window. To elucidate potential antibacterial modes of action, Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), infrared spectroscopy, and atomic force microscopy (AFM) were used. The results suggest improved Ga3+ interaction with PAO1 through Ga-NAC particles. No significant change in cell membrane chemistry or roughening was detected. As cell membrane integrity remained intact, the antimicrobial mode of action was linked to cellular internalization of Ga and subsequent iron metabolic disruption. Furthermore, Ga-NAC inhibited and disrupted biofilms seen with crystal violet assay and microscopy. Our findings suggest the Ga-NAC particle can potentially be used as an alternative to antibiotics for treatment of Pseudomonas aeruginosa infections.

6.
J Agric Food Chem ; 67(25): 6970-6977, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31150237

RESUMO

Huanglongbing (HLB), also known as citrus greening, is a bacterial disease that poses a devastating threat to the citrus industry worldwide. To manage this disease efficiently, we developed and characterized a ternary aqueous solution (TSOL) that contains zinc nitrate, urea, and hydrogen peroxide. We report that TSOL exhibits better antimicrobial activity than commercial bactericides for growers. X-ray fluorescence analysis demonstrates that zinc is delivered to citrus leaves, where the bacteria reside. FTIR and Raman spectroscopy, molecular dynamics simulations, and density functional theory calculations elucidate the solution structure of TSOL and reveal a water-mediated interaction between Zn2+ and H2O2, which may facilitate the generation of highly reactive hydroxyl radicals contributing to superior antimicrobial activity of TSOL. Our results not only suggest TSOL as a potent antimicrobial agent to suppress bacterial growth in HLB-infected trees, but also provide a structure-property relationship that explains the superior performance of TSOL.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Citrus/microbiologia , Nitratos/química , Nitratos/farmacologia , Doenças das Plantas/prevenção & controle , Rhizobiaceae/fisiologia , Compostos de Zinco/química , Compostos de Zinco/farmacologia , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/farmacologia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Rhizobiaceae/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Relação Estrutura-Atividade , Ureia/química , Ureia/farmacologia
7.
J Fungi (Basel) ; 4(3)2018 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-30149666

RESUMO

Simple sugars produced from a solvent-free mechanocatalytic degradation of cellulose were evaluated for suitability as a growth medium carbon source for fungi that produce volatile organic compounds. An endophytic Hypoxylon sp. (CI-4) known to produce volatiles having potential value as fuels was initially evaluated. The growth was obtained on a medium containing the degraded cellulose as the sole carbon source, and the volatile compounds produced were largely the same as those produced from a conventional dextrose/starch diet. A second Hypoxylon sp. (BS15) was also characterized and shown to be phylogenetically divergent from any other named species. The degraded cellulose medium supported the growth of BS15, and approximately the same quantity of the volatile compounds was produced as from conventional diets. Although the major products from BS15 grown on the degraded cellulose were identical to those from dextrose, the minor products differed. Neither CI-4 or BS15 exhibited growth on cellulose that had not been degraded. The extraction of volatiles from the growth media was achieved using solid-phase extraction in order to reduce the solvent waste and more efficiently retain compounds having low vapor pressures. A comparison to more conventional liquid⁻liquid extraction demonstrated that, for CI-4, both methods gave similar results. The solid-phase extraction of BS15 retained a significantly larger variety of the volatile compounds than did the liquid⁻liquid extraction. These advances position the coupling of solvent-free cellulose conversion and endophyte metabolism as a viable strategy for the production of important hydrocarbons.

8.
Nanomaterials (Basel) ; 5(4): 2359-2379, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-28347126

RESUMO

Quantum dot (Qdot) biosensors have consistently provided valuable information to researchers about cellular activity due to their unique fluorescent properties. Many of the most popularly used Qdots contain cadmium, posing the risk of toxicity that could negate their attractive optical properties. The design of a non-cytotoxic probe usually involves multiple components and a complex synthesis process. In this paper, the design and synthesis of a non-cytotoxic Qdot-chitosan nanogel composite using straight-forward cyanogen bromide (CNBr) coupling is reported. The probe was characterized by spectroscopy (UV-Vis, fluorescence), microscopy (Fluorescence, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Dynamic Light Scattering. This activatable ("OFF"/"ON") probe contains a core-shell Qdot (CdS:Mn/ZnS) capped with dopamine, which acts as a fluorescence quencher and a model drug. Dopamine capped "OFF" Qdots can undergo ligand exchange with intercellular glutathione, which turns the Qdots "ON" to restore fluorescence. These Qdots were then coated with chitosan (natural biocompatible polymer) functionalized with folic acid (targeting motif) and Fluorescein Isothiocyanate (FITC; fluorescent dye). To demonstrate cancer cell targetability, the interaction of the probe with cells that express different folate receptor levels was analyzed, and the cytotoxicity of the probe was evaluated on these cells and was shown to be nontoxic even at concentrations as high as 100 mg/L.

9.
J Biol Chem ; 289(22): 15328-39, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24753255

RESUMO

The chemokine CXCL10/IP-10 facilitates recruitment of Th1-type leukocytes to inflammatory sites. In this study, we show that the arginine methyltransferase PRMT5 is critical for CXCL10 transcription in TNF-α-activated human endothelial cells (EC). We found that depletion of PRMT5 results in significantly reduced levels of CXCL10 mRNA, demonstrating a positive role for PRMT5 in CXCL10 induction. Chromatin immunoprecipitation experiments revealed the presence of the symmetrical dimethylarginine modification catalyzed by PRMT5 associated with the CXCL10 promoter in response to TNF-α. However, symmetrical dimethylarginine-modified proteins were not detected at the promoter in the absence of PRMT5, indicating that PRMT5 is essential for methylation to occur. Furthermore, NF-κB p65, a critical driver of TNF-α-mediated CXCL10 induction, was determined to be methylated at arginine residues. Crucially, RNAi-mediated PRMT5 depletion abrogated p65 methylation and CXCL10 promoter binding. Mass spectrometric analysis in EC identified five dimethylated arginine residues in p65, four of which are uncharacterized in the literature. Expression of Arg-to-Lys point mutants of p65 demonstrated that both Arg-30 and Arg-35 must be dimethylated to achieve full CXCL10 expression. In conclusion, we have identified previously uncharacterized p65 post-translational modifications critical for CXCL10 induction.


Assuntos
Quimiocina CXCL10/genética , Células Endoteliais/fisiologia , Proteína-Arginina N-Metiltransferases/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Arginina/metabolismo , Quimiocina CXCL10/metabolismo , Células Endoteliais/citologia , Humanos , Inflamação/genética , Inflamação/metabolismo , Metilação , Cultura Primária de Células , Regiões Promotoras Genéticas/fisiologia , Processamento de Proteína Pós-Traducional/fisiologia , Proteína-Arginina N-Metiltransferases/genética , Transcrição Gênica/fisiologia
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