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1.
Infect Immun ; 90(4): e0059721, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35311543

RESUMO

Streptococcus pneumoniae is a Gram-positive, encapsulated bacterium that is a significant cause of disease burden in pediatric and elderly populations. The rise in unencapsulated disease-causing strains and antimicrobial resistance in S. pneumoniae has increased the need for developing new antimicrobial strategies. Recent work by our laboratory has identified N,N-dimethyldithiocarbamate (DMDC) as a copper-dependent antimicrobial against bacterial, fungal, and parasitic pathogens. As a bactericidal antibiotic against S. pneumoniae, DMDC's ability to work as a copper-dependent antibiotic and its ability to work in vivo warranted further investigation. Here, our group studied the mechanisms of action of DMDC under various medium and excess-metal conditions and investigated DMDC's interactions with the innate immune system in vitro and in vivo. Of note, we found that DMDC plus copper significantly increased the internal copper concentration, hydrogen peroxide stress, nitric oxide stress, and the in vitro macrophage killing efficiency and decreased capsule. Furthermore, we found that in vivo DMDC treatment increased the quantity of innate immune cells in the lung during infection. Taken together, this study provides mechanistic insights regarding DMDC's activity as an antibiotic at the host-pathogen interface.


Assuntos
Anti-Infecciosos , Infecções Pneumocócicas , Idoso , Antibacterianos , Anti-Infecciosos/farmacologia , Criança , Cobre , Dimetilditiocarbamato , Humanos , Macrófagos , Streptococcus pneumoniae
2.
Neurosurg Focus ; 45(6): E10, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30544309

RESUMO

OBJECTIVESymptomatic cervical spondylosis with or without radiculopathy can ground an active-duty military pilot if left untreated. Surgically treated cervical spondylosis may be a waiverable condition and allow return to flying status, but a waiver is based on expert opinion and not on recent published data. Previous studies on rates of return to active duty status following anterior cervical spine surgery have not differentiated these rates among military specialty occupations. No studies to date have documented the successful return of US military active-duty pilots who have undergone anterior cervical spine surgery with cervical fusion, disc replacement, or a combination of the two. The aim of this study was to identify the rate of return to an active duty flight status among US military pilots who had undergone anterior cervical discectomy and fusion (ACDF) or total disc replacement (TDR) for symptomatic cervical spondylosis.METHODSThe authors performed a single-center retrospective review of all active duty pilots who had undergone either ACDF or TDR at a military hospital between January 2010 and June 2017. Descriptive statistics were calculated for both groups to evaluate demographics with specific attention to preoperative flight stats, days to recommended clearance by neurosurgery, and days to return to active duty flight status.RESULTSAuthors identified a total of 812 cases of anterior cervical surgery performed between January 1, 2010, and June 1, 2017, among active duty, reserves, dependents, and Department of Defense/Veterans Affairs patients. There were 581 ACDFs and 231 TDRs. After screening for military occupation and active duty status, there were a total of 22 active duty pilots, among whom were 4 ACDFs, 17 TDRs, and 2 hybrid constructs. One patient required a second surgery. Six (27.3%) of the 22 pilots were nearing the end of their career and electively retired within a year of surgery. Of the remaining 16 pilots, 11 (68.8%) returned to active duty flying status. The average time to be released by the neurosurgeon was 128 days, and the time to return to flying was 287 days. The average follow-up period was 12.3 months.CONCLUSIONSAdhering to military service-specific waiver guidelines, military pilots may return to active duty flight status after undergoing ACDF or TDR for symptomatic cervical spondylosis.


Assuntos
Vértebras Cervicais/cirurgia , Discotomia , Militares , Doenças da Coluna Vertebral/cirurgia , Adulto , Artroplastia/métodos , Discotomia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pilotos , Radiculopatia/cirurgia , Fusão Vertebral/estatística & dados numéricos , Substituição Total de Disco/métodos , Resultado do Tratamento
3.
SIAM J Appl Dyn Syst ; 17(1): 909-930, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-33584153

RESUMO

We develop a new generalization of Koopman operator theory that incorporates the e ects of inputs and control. Koopman spectral analysis is a theoretical tool for the analysis of nonlinear dynamical systems. Moreover, Koopman is intimately connected to dynamic mode decomposition (DMD), a method that discovers coherent, spatio-temporal modes from data, connects local-linear analysis to nonlinear operator theory, and importantly creates an equation-free architecture for the study of complex systems. For actuated systems, standard Koopman analysis and DMD are incapable of producing input-output models; moreover, the dynamics and the modes will be corrupted by external forcing. Our new theoretical developments extend Koopman operator theory to allow for systems with nonlinear input-output characteristics. We show how this generalization is rigorously connected to a recent development called dynamic mode decomposition with control. We demonstrate this new theory on nonlinear dynamical systems, including a standard susceptible-infectious-recovered model with relevance to the analysis of infectious disease data with mass vaccination (actuation).

4.
Basic Clin Neurosci ; 15(3): 367-382, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39403359

RESUMO

Introduction: Neurodevelopmental disorders comprise a group of neuropsychiatric conditions. Presently, behavior-based diagnostic approaches are utilized in clinical settings, but the overlapping features among these disorders obscure their recognition and management. Attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) have common characteristics across various levels, from genes to symptoms. Designing a computational framework based on the neuroimaging findings could provide a discriminative tool for ultimate more efficient treatment. Machine learning approaches, specifically classification methods are among the most applied techniques to reach this goal. Methods: We applied a novel two-level multi-class data maximum dispersion classifier (DMDC) algorithm to classify the functional neuroimaging data (utilizing datasets: ADHD-200 and autism brain imaging data exchange (ABIDE)) into two categories: Neurodevelopmental disorders (ASD and ADHD) or healthy participants, based on calculated functional connectivity values (statistical temporal correlation). Results: Our model achieved a total accuracy of 62% for healthy controls. Specifically, it demonstrated an accuracy of 51% for healthy subjects, 61% for autism spectrum disorder, and 84% for ADHD. The support vector machine (SVM) model achieved an accuracy of 46% for both the healthy control and ASD groups, while the ADHD group classification accuracy was estimated to be 84%. These two models showed similar classification indices for the ADHD group. However, the discrimination power was higher in the ASD class. Conclusion: The method employed in this study demonstrated acceptable performance in classifying disorders and healthy conditions compared to the more commonly used SVM method. Notably, functional connections associated with the cerebellum showed discriminative power.

5.
Vaccines (Basel) ; 8(4)2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33167425

RESUMO

Adult T-cell leukemia (ATL) is a CD4+ T-cell neoplasm caused by human T-cell leukemia virus type I. As the prognosis for patients with ATL remains extremely poor due to resistance to conventional chemotherapy regimens, introduction of novel therapeutic agents is needed. Previous studies have reported that nucleosides 2'-deoxy-2'-methylidenecytidine (DMDC) and its derivative 2'-deoxy-2'-methylidene-5-fluorocytidine (FDMDC) exhibit antitumor activities in T-cell acute lymphoblastic leukemia (T-ALL) and solid tumor cell lines. Another nucleoside, 1-(2-azido-2-deoxy-ß-D-arabinofuranosyl)cytosine (cytarazid), is considered a therapeutic drug with antitumor activity in human solid tumors. In this study, we investigated the effects of these nucleosides on cell growth in vitro and in vivo using relevant leukemia cell lines and NOD/Shi-scid, IL-2Rgnull (NOG) mice, respectively. The nucleosides demonstrated significant cytotoxic effects in ATL and T-ALL cell lines. Intraperitoneal administration of FDMDC and DMDC into tumor-bearing NOG mice resulted in significant suppression of tumor growth without lethal side effects. Our findings support a therapeutic application of these nucleosides against tumor progression by targeting DNA polymerase-dependent DNA synthesis in patients with ATL.

6.
Int J Food Microbiol ; 270: 1-4, 2018 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-29427947

RESUMO

During wine production, some yeasts enter a Viable But Not Culturable (VBNC) state, which may influence the quality and stability of the final wine through remnant metabolic activity or by resuscitation. Culture-independent techniques are used for obtaining an accurate estimation of the number of live cells, and quantitative PCR could be the most accurate technique. As a marker of cell viability, rRNA was evaluated by analyzing its stability in dead cells. The species-specific stability of rRNA was tested in Saccharomyces cerevisiae, as well as in three species of non-Saccharomyces yeast (Hanseniaspora uvarum, Torulaspora delbrueckii and Starmerella bacillaris). High temperature and antimicrobial dimethyl dicarbonate (DMDC) treatments were efficient in lysing the yeast cells. rRNA gene and rRNA (as cDNA) were analyzed over 48 h after cell lysis by quantitative PCR. The results confirmed the stability of rRNA for 48 h after the cell lysis treatments. To sum up, rRNA may not be a good marker of cell viability in the wine yeasts that were tested.


Assuntos
Hanseniaspora/genética , Estabilidade de RNA/genética , RNA Ribossômico/genética , Saccharomyces cerevisiae/genética , Torulaspora/genética , Vinho/microbiologia , Contagem de Células , Sobrevivência Celular/genética , Dietil Pirocarbonato/análogos & derivados , Dietil Pirocarbonato/farmacologia , Fermentação , Marcadores Genéticos/genética , Hanseniaspora/metabolismo , Reação em Cadeia da Polimerase , Saccharomyces cerevisiae/metabolismo , Torulaspora/metabolismo , Fermento Seco , Leveduras/genética
7.
J Food Sci ; 82(9): 2128-2133, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28833163

RESUMO

In order to preserve a commercial dealcoholized red wine (DRW), a study with 4 preservatives and binary mixtures of them were performed against 2 native spoilage yeasts: Rhodotorula mucilaginosa and Saccharomyces cerevisiae. Minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) for potassium sorbate, sodium benzoate, sodium metabisulfite and dimethyl dicarbonate (DMDC) were evaluated in DRW stored at 25 °C. MICs of potassium sorbate and sodium metabisulfite were 250 and 60 mg/kg, respectively for both target strains. However for sodium benzoate, differences between yeasts were found; R. mucilaginosa was inhibited at 125 mg/kg, while S. cerevisiae at 250 mg/kg. Regarding MFC, differences between strains were only found for sodium metabisulfite obtaining a MFC of 500 mg/kg for R. mucilaginosa and a MFC of 250 mg/kg for S. cerevisiae. Potassium sorbate and sodium benzoate showed the MFC at 1000 mg/kg and DMDC at 200 mg/kg. Regarding the effect of binary mixtures the Fractional Fungicidal Concentration Index (FFCi ) methodology showed that binary mixtures of 100 mg/kg DMDC/200 mg/kg potassium sorbate (FFCi = 0.7) and 50 mg/kg DMDC / 400 mg/kg sodium benzoate (FFCi = 0.65) have both synergistic effect against the 2 target strains. These binary mixtures can control the growth of spoilage yeasts in DRW without metabisulfite addition. The results of this work may be important in preserving the health of DRW consumers by eliminating the use of metabisulfite and reducing the risk of growth of R. mucilagosa, recently recognized as an emerging pathogen.


Assuntos
Conservantes de Alimentos/farmacologia , Vinho/análise , Leveduras/efeitos dos fármacos , Dietil Pirocarbonato/análogos & derivados , Dietil Pirocarbonato/farmacologia , Conservação de Alimentos , Testes de Sensibilidade Microbiana , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Benzoato de Sódio/farmacologia , Ácido Sórbico/farmacologia , Sulfitos/farmacologia , Vinho/microbiologia , Leveduras/crescimento & desenvolvimento
8.
Artigo em Inglês | MEDLINE | ID: mdl-26374496

RESUMO

The use of sulphur dioxide (SO2) in the treatment of foodstuffs presents some problems as it could lead to pseudo-allergies in some people. The aim of this research work was to study the addition of different preservative mixtures and their influence on the concentration of volatile compounds and sensorial quality in wine. To do so, vinifications were carried out using Garnacha must to which lysozyme, dimethyl dicarbonate (DMDC) and mixtures of these with SO2 were added at different doses (25 and 50 mg l(-1)). The results were compared with a control sample to which only SO2 had been added (50 mg l(-1)). In general, mixtures of SO2 with lysozyme and DMDC favoured the formation of volatile compounds in the wines. Wines obtained from the mixtures of lysozyme and DMDC with 25 mg l(-1) of SO2 had better sensorial quality than the wines obtained with 50 mg l(-1) as the only preservative used.


Assuntos
Dietil Pirocarbonato/análogos & derivados , Conservantes de Alimentos/química , Muramidase/química , Dióxido de Enxofre/química , Vinho/análise , Dietil Pirocarbonato/química , Conservação de Alimentos/métodos , Humanos , Odorantes/análise , Compostos Orgânicos Voláteis/química
9.
J Food Sci ; 78(8): M1236-41, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23957413

RESUMO

The individual and combined influences of dimethyl dicarbonate (DMDC) and nisin (200 IU/mL) at mild heat on the inactivation of indigenous microorganisms in litchi juice, including bacteria, molds and yeasts (M&Y), were investigated. The fresh litchi juice with or without nisin were exposed to 250 mg/L DMDC at 30, 40, or 45 °C for 0.5, 1, 2, 3, 4, or 6 h. A complete inactivation of M&Y in the litchi juice with or without nisin was achieved as exposed to 250 mg/L DMDC at 30, 40, or 45 °C for 0.5 h. The bacteria, especially Bacillus sp. and Leuconstoc mesenteroides showed higher resistance than M&Y in the litchi juice. Bacillus sp. and Leuconstoc mesenteroides in the litchi juice was not completely inactivated by 250 mg/L DMDC at 30, 40, or 45 °C. However, nisin addition can enhanced the inactivation of these bacteria by DMDC, and nisin and DMDC also showed a synergistic effect on the inactivation of bacteria. M&Y and bacteria were not detected in the litchi juice added with 200 IU/mL nisin as exposed to 250 mg/L DMDC at 45 °C for 3 h. In addition, microbial shelf life of the litchi juice during storage at 4 °C also was evaluated as treated by 250 mg/L DMDC or combination with nisin at 45 °C for 3 h.


Assuntos
Bebidas/microbiologia , Dietil Pirocarbonato/análogos & derivados , Conservação de Alimentos , Litchi/microbiologia , Nisina/farmacologia , Antibacterianos/farmacologia , Bacillus/efeitos dos fármacos , Bacillus/crescimento & desenvolvimento , Bacillus/isolamento & purificação , Contagem de Colônia Microbiana , Dietil Pirocarbonato/farmacologia , Sinergismo Farmacológico , Contaminação de Alimentos/prevenção & controle , Manipulação de Alimentos , Microbiologia de Alimentos , Frutas , Leuconostoc/efeitos dos fármacos , Leuconostoc/crescimento & desenvolvimento , Leuconostoc/isolamento & purificação , Organização Mundial da Saúde
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