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1.
PLoS Genet ; 18(9): e1010372, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36178933

RESUMO

Homeobox genes are prominent regulators of neuronal identity, but the extent to which their function has been probed in animal nervous systems remains limited. In the nematode Caenorhabditis elegans, each individual neuron class is defined by the expression of unique combinations of homeobox genes, prompting the question of whether each neuron class indeed requires a homeobox gene for its proper identity specification. We present here progress in addressing this question by extending previous mutant analysis of homeobox gene family members and describing multiple examples of homeobox gene function in different parts of the C. elegans nervous system. To probe homeobox function, we make use of a number of reporter gene tools, including a novel multicolor reporter transgene, NeuroPAL, which permits simultaneous monitoring of the execution of multiple differentiation programs throughout the entire nervous system. Using these tools, we add to the previous characterization of homeobox gene function by identifying neuronal differentiation defects for 14 homeobox genes in 24 distinct neuron classes that are mostly unrelated by location, function and lineage history. 12 of these 24 neuron classes had no homeobox gene function ascribed to them before, while in the other 12 neuron classes, we extend the combinatorial code of transcription factors required for specifying terminal differentiation programs. Furthermore, we demonstrate that in a particular lineage, homeotic identity transformations occur upon loss of a homeobox gene and we show that these transformations are the result of changes in homeobox codes. Combining the present with past analyses, 113 of the 118 neuron classes of C. elegans are now known to require a homeobox gene for proper execution of terminal differentiation programs. Such broad deployment indicates that homeobox function in neuronal identity specification may be an ancestral feature of animal nervous systems.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Diferenciação Celular/genética , Proteínas de Ligação a DNA/genética , Emprego , Regulação da Expressão Gênica no Desenvolvimento , Genes Homeobox/genética , Neurônios/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
Biol Res ; 56(1): 51, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37773178

RESUMO

BACKGROUND: Nitric oxide is produced by different nitric oxide synthases isoforms. NO activates two signaling pathways, one dependent on soluble guanylate cyclase and protein kinase G, and other where NO post-translationally modifies proteins through S-nitrosylation, which is the modification induced by NO in free-thiol cysteines in proteins to form S-nitrosothiols. High levels of NO have been detected in blood of breast cancer patients and increased NOS activity has been detected in invasive breast tumors compared to benign or normal breast tissue, suggesting a positive correlation between NO biosynthesis, degree of malignancy and metastasis. During metastasis, the endothelium plays a key role allowing the adhesion of tumor cells, which is the first step in the extravasation process leading to metastasis. This step shares similarities with leukocyte adhesion to the endothelium, and it is plausible that it may also share some regulatory elements. The vascular cell adhesion molecule-1 (VCAM-1) expressed on the endothelial cell surface promotes interactions between the endothelium and tumor cells, as well as leukocytes. Data show that breast tumor cells adhere to areas in the vasculature where NO production is increased, however, the mechanisms involved are unknown. RESULTS: We report that the stimulation of endothelial cells with interleukin-8, and conditioned medium from breast tumor cells activates the S-nitrosylation pathway in the endothelium to induce leukocyte adhesion and tumor cell extravasation by a mechanism that involves an increased VCAM-1 cell surface expression in endothelial cells. We identified VCAM-1 as an S-nitrosylation target during this process. The inhibition of NO signaling and S-nitrosylation blocked the transmigration of tumor cells through endothelial monolayers. Using an in vivo model, the number of lung metastases was inhibited in the presence of the S-nitrosylation inhibitor N-acetylcysteine (NAC), which was correlated with lower levels of S-nitrosylated VCAM-1 in the metastases. CONCLUSIONS: S-Nitrosylation in the endothelium activates pathways that enhance VCAM-1 surface localization to promote binding of leukocytes and extravasation of tumor cells leading to metastasis. NAC is positioned as an important tool that might be tested as a co-therapy against breast cancer metastasis.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Adesão Celular , Células Endoteliais , Molécula 1 de Adesão de Célula Vascular/metabolismo , Óxido Nítrico/metabolismo , Melanoma Maligno Cutâneo
3.
Chem Biodivers ; 20(1): e202200631, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36423339

RESUMO

This study aimed to determine the phenolic compounds profile, antioxidant potential and cytotoxicity of extracts and fractions of Caesalpinia palmeri. Methanolic extracts were generated from C. palmeri berries, stems and flowers. The latter was subjected to liquid-liquid partition, obtaining hexane, ethyl acetate and residues fractions. Results showed that the flower extract and ethyl acetate fraction had a larger concentration of phenolic compounds (148.9 and 307.9 mg GAE/g, respectively), being ellagic acid (6233.57 and 19550.08 µg/g, respectively), quercetin-3-ß-glycoside (3023.85 and 8952.55 µg/g, respectively) and gallic acid (2212.98 and 8422.34 µg/g, respectively) the most abundant compounds. Flower extract and ethyl acetate fraction also presented the highest antioxidant capacity on all tested methods (DPPH, ABTS, ORAC and FRAP) and low cytotoxicity against ARPE-19 cells (IC50 >170 µg/mL). C. palmeri possessed high antioxidant potential, associated with the presence of phenolic compounds and low cytotoxicity, suggesting that they could represent an option to counter oxidative stress.


Assuntos
Antioxidantes , Caesalpinia , Antioxidantes/farmacologia , Antioxidantes/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Acetatos
4.
BMC Microbiol ; 20(1): 213, 2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32689948

RESUMO

BACKGROUND: Staphylococcus aureus is a leading cause of broad-spectrum infections both in the community and within healthcare settings. Methicillin-resistant Staphylococcus aureus (MRSA) has become a global public health issue. The aim of this study was to examine the clinical and molecular characteristics of Staphylococcus aureus isolates and to define the population structure and distribution of major MRSA clones isolated in a tertiary-care hospital in Mexico. RESULTS: From April 2017 to April 2018, 191 Staphylococcus aureus isolates were collected. The frequency of MRSA was 26.7%; these strains exhibited resistance to clindamycin (84.3%), erythromycin (86.2%), levofloxacin (80.3%), and ciprofloxacin (86.3%). The majority of MRSA strains harbored the SCCmec type II (76.4%) and t895 (56.8%) and t9364 (11.7%) were the most common spa types in both hospital-associated MRSA and community-associated MRSA isolates. ST5-MRSA-II-t895 (New York /Japan clone) and ST1011-MRSA-II-t9364 (New York /Japan-Mexican Variant clone) were the most frequently identified clones. Furthermore, different lineages of Clonal Complexes 5 (85.4%) and 8 (8.3%) were predominantly identified in this study. CONCLUSION: Our study provides valuable information about the epidemiology of MRSA in a city of the central region of Mexico, and this is the first report on the association between t895 and t9364 spa types and ST5 and ST1011 lineages, respectively. These findings support the importance of permanent surveillance of MRSA aimed to detect the evolutionary changes of the endemic clones and the emergence of new strains.


Assuntos
Antibacterianos/farmacologia , Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/microbiologia , Staphylococcus aureus Resistente à Meticilina/classificação , Tipagem Molecular/métodos , Infecções Estafilocócicas/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/epidemiologia , Infecção Hospitalar/epidemiologia , Farmacorresistência Bacteriana Múltipla , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , México/epidemiologia , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Filogenia , Prevalência , Centros de Atenção Terciária , Adulto Jovem
5.
Phys Rev Lett ; 124(12): 120402, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32281831

RESUMO

We show-both theoretically and experimentally-that Einstein-Podolsky-Rosen steering can be distilled. We present a distillation protocol that outputs a perfectly correlated system-the singlet assemblage-in the asymptotic infinite-copy limit, even for inputs that are arbitrarily close to being unsteerable. As figures of merit for the protocol's performance, we introduce the assemblage fidelity and the singlet-assemblage fraction. These are potentially interesting quantities on their own beyond the current scope. Remarkably, the protocol works well also in the nonasymptotic regime of few copies, in the sense of increasing the singlet-assemblage fraction. We demonstrate the efficacy of the protocol using a hyperentangled photon pair encoding two copies of a two-qubit state. This represents to our knowledge the first observation of deterministic steering concentration. Our findings are not only fundamentally important but may also be useful for semi-device-independent protocols in noisy quantum networks.

6.
J Appl Microbiol ; 128(2): 387-400, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31573730

RESUMO

AIMS: To study the individual and combined contribution of catechin, protocatechuic and vanillic acids to inhibit the adhesion of uropathogenic Escherichia coli (UPEC) on the surface of silicone catheters. METHODS AND RESULTS: The adhesion of UPEC to silicone catheters during the exposure to nonlethal concentrations of phenolic compounds was measured, as well as changes in motility, presence of fimbriae, extra-cellular polymeric substances, surface charge, hydrophobicity and membrane fluidity. The phenolic combination reduced 26-51% of motility, 1 log CFU per cm2 of adhered bacteria and 20-40% the carbohydrate and protein content in the biofilm matrix. Curli fimbriae, surface charge and cell hydrophobicity were affected to a greater extent by the phenolic combination. In the mixture, vanillic acid was the most effective for reducing bacterial adhesion, extra-polymeric substance production, motility, curli fimbriae and biofilm structure. Notwithstanding, protocatechuic acid caused major changes in the bacterial cell surface properties, whereas catechin affected the cell membrane functionality. CONCLUSION: Catechin, protocatechuic and vanillic acids have different bacterial cell targets, explaining the synergistic effect of their combination against uropathogenic E. coli. SIGNIFICANCE AND IMPACT OF STUDY: This study shows the contribution of catechin, protocatechuic and vanillic acids in producing a synergistic mixture against the adhesion of uropathogenic E. coli on silicone catheters. The action of catechin, vanillic and protocatechuic acids included specific contributions of each compound against the E. coli membrane's integrity, motility, surface properties and production of extracellular polymeric substances. Therefore, the studied mixture of phenolic compounds could be used as an antibiotic alternative to reduce urinary tract infections associated with silicone catheters.


Assuntos
Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Catequina/farmacologia , Hidroxibenzoatos/farmacologia , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/efeitos dos fármacos , Ácido Vanílico/farmacologia , Catéteres/microbiologia , Sinergismo Farmacológico , Infecções por Escherichia coli/microbiologia , Fímbrias Bacterianas/efeitos dos fármacos , Fímbrias Bacterianas/genética , Fímbrias Bacterianas/metabolismo , Humanos , Fenóis/farmacologia , Silicones/análise , Escherichia coli Uropatogênica/crescimento & desenvolvimento , Escherichia coli Uropatogênica/fisiologia
7.
Food Microbiol ; 87: 103377, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31948618

RESUMO

The present study explored the effect of quercetin on the expression of virulence genes actA, inlA, inlC, and their regulatory components, sigB and prfA, in L. monocytogenes. Furthermore, the physicochemical changes on the surface, membrane permeability, and biofilm formation of quercetin-treated bacteria were evaluated. An inhibitory dose-dependent effect of quercetin (0.1-0.8 mM) was observed on the cell attachment on stainless steel at 2 and 6 h at 37 °C. Quercetin at 0.8 mM prevented the biofilm formation on stainless steel surfaces after 6 h of incubation at 37 °C, while the untreated bacteria formed biofilms with a cell density of 5.1 Log CFU/cm2. The microscopic analysis evidenced that quercetin at 0.2 mM decreased the biovolume and covered area of the attached micro-colonies. Also, sigB, prfA, inlA, inlC, and actA genes were downregulated by 7-29 times lower compared to untreated bacteria. In addition, quercetin decreased the superficial cell charge, increased the membrane permeability, and its surface hydrophobicity. These results demonstrated that quercetin prevented biofilm formation, repressed the genes of stress and virulence of L. monocytogenes and also altered the physicochemical cell properties.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Proteínas de Bactérias/genética , Biofilmes/efeitos dos fármacos , Listeria monocytogenes/efeitos dos fármacos , Quercetina/farmacologia , Fatores de Virulência/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Listeria monocytogenes/genética , Listeria monocytogenes/fisiologia , Aço Inoxidável/química , Fatores de Virulência/metabolismo
8.
Antonie Van Leeuwenhoek ; 111(8): 1273-1291, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29445901

RESUMO

The Atacama Desert, the driest of its kind on Earth, hosts a number of unique geological and geochemical features that make it unlike any other environment on the planet. Considering its location on the western border of South America, between 17 and 28 °S, its climate has been characterized as arid to hyperarid for at least the past 10 million years. Notably dry climatic conditions of the Atacama Desert have been related to uplift of the Andes and are believed to have played an important role in the development of the most distinctive features of this desert, including: (i) nitrates and iodine deposits in the Central Depression, (ii) secondary enrichment in porphyry copper deposits in the Precordillera, (iii) Li enrichment in salt flats of the Altiplano, and (iv) life in extreme habitats. The geology and physiography of the Atacama Desert have been largely shaped by the convergent margin present since the Mesozoic era. The geochemistry of surface materials is related to rock geochemistry (Co, Cr, Fe, Mn, V, and Zn), salt flats, and evaporite compositions in endorheic basins (As, B, and Li), in addition to anthropogenic activities (Cu, Mo, and Pb). The composition of surface water is highly variable, nonetheless in general it presents a circumneutral pH with higher conductivity and total dissolved solids in brines. Major water constituents, with the exception of HCO3-, are generally related to the increase of salinity, and despite the fact that trace elements are not well-documented, surface waters of the Atacama Desert are enriched in As, B, and Li when compared to the average respective concentrations in rivers worldwide.


Assuntos
Clima Desértico , Sedimentos Geológicos/química , Geologia , Solo/química , Salinidade , América do Sul , Oligoelementos/análise , Água/química
9.
Acta Anaesthesiol Scand ; 62(5): 608-619, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29377061

RESUMO

BACKGROUND: We conducted this study to test whether pulse-oximetry hemoglobin saturation (SpO2 ) can personalize the implementation of an open-lung approach during laparoscopy. Thirty patients with SpO2  ≥ 97% on room-air before anesthesia were studied. After anesthesia and capnoperitoneum the FIO2 was reduced to 0.21. Those patients whose SpO2 decreased below 97% - an indication of shunt related to atelectasis - completed the following phases: (1) First recruitment maneuver (RM), until reaching lung's opening pressure, defined as the inspiratory pressure level yielding a SpO2 ≥ 97%; (2) decremental positive end-expiratory (PEEP) titration trial until reaching lung's closing pressure defined as the PEEP level yielding a SpO2  < 97%; (3) second RM and, (4) ongoing ventilation with PEEP adjusted above the detected closing pressure. RESULTS: When breathing air, in 24 of 30 patients SpO2 was < 97%, PaO2 /FIO2  Ë‚ 53.3 kPa and negative end-expiratory transpulmonary pressure (PTP-EE ). The mean (SD) opening pressures were found at 40 (5) and 33 (4) cmH2 O during the first and second RM, respectively (P < 0.001; 95% CI: 3.2-7.7). The closing pressure was found at 11 (5) cmH2 O. This SpO2 -guided approach increased PTP-EE (from -6.4 to 1.2 cmH2 O, P < 0.001) and PaO2 /FIO2 (from 30.3 to 58.1 kPa, P < 0.001) while decreased driving pressure (from 18 to 10 cmH2 O, P < 0.001). SpO2 discriminated the lung's opening and closing pressures with accuracy taking the reference parameter PTP-EE (area under the receiver-operating-curve of 0.89, 95% CI: 0.80-0.99). CONCLUSION: The non-invasive SpO2 monitoring can help to individualize an open-lung approach, including all involved steps, from the identification of those patients who can benefit from recruitment, the identification of opening and closing pressures to the subsequent monitoring of an open-lung condition.


Assuntos
Laparoscopia/métodos , Oximetria/métodos , Respiração com Pressão Positiva/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC
10.
Lett Appl Microbiol ; 66(1): 25-31, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29063625

RESUMO

Fruit extracts from different tissues (pulp, seed and peel) have shown antimicrobial and prebiotic activities related to their phenolic profile, although structure-specific evaluations have not been reported yet. The effect of five phenolic compounds (catechin and gallic, vanillic, ferulic and protocatechuic acids) identified in different fruits, particularly in mango, was evaluated on the growth of two probiotic (Lactobacillus rhamnosusGG ATCC 53103 and Lactobacillus acidophilusNRRLB 4495) and two pathogenic (Escherichia coli 0157:H7 ATCC 43890 and Salmonella enterica serovar Typhimurium ATCC 14028) bacteria. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of phenolic acids ranged from 15-20 mmol l-1 and 20-30 mmol l-1 against E. coli and S. Typhimurium, respectively. For catechin, the MIC and MBC were 35 mmol l-1 and >35 mmol l-1 against E. coli and S. Typhimurium, respectively. The presence of catechin and gallic, protocatechuic and vanillic acids in MRS broth without dextrose allowed the growth of lactobacilli. Catechin combined with protocatechuic or vanillic acid mildly allowed the growth of both probiotics. In conclusion, phenolic compounds can selectively inhibit the growth of pathogenic bacteria without affecting the viability of probiotics. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides relevant information about the effects of phenolic compounds commonly present in fruit and vegetables on the growth of probiotic and pathogenic bacteria. The compounds selectively allowed the growth of probiotic lactobacilli (Lactobacillus rhamnosus GG and Lactobacillus acidophilus) and inhibited pathogenic bacteria (Escherichia coli and Salmonella Typhimurium) at the same concentration (20 mmol l-1 ). These findings can contribute to the formulation of nutraceutical products, such as synbiotics, that can restore or maintain an optimal composition of human microbiota, potentially improving the overall health of the consumer.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Lactobacillus/efeitos dos fármacos , Fenóis/farmacologia , Probióticos/análise , Salmonella typhimurium/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Humanos , Hidroxibenzoatos/farmacologia , Lactobacillus/crescimento & desenvolvimento , Fenóis/química , Salmonella typhimurium/crescimento & desenvolvimento
11.
Phys Rev Lett ; 119(8): 083601, 2017 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-28952756

RESUMO

We propose and experimentally demonstrate a novel approach to a heralded single-photon source based on spectral multiplexing (SMUX) and feed-forward-based spectral manipulation of photons created by means of spontaneous parametric down-conversion in a periodically poled LiNbO_{3} crystal. As a proof of principle, we show that our three-mode SMUX increases the heralded single-photon rate compared to that of the individual modes without compromising the quality of the emitted single photons. We project that by adding further modes, our approach can lead to a deterministic single-photon source.

12.
Appl Opt ; 56(25): 7167-7173, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29047977

RESUMO

A high-velocity fluid stream ejected from an orifice or nozzle is a common mechanism to produce liquid jets in inkjet printers or to produce sprays among other applications. In the present research, we show the generation of liquid jets of controllable direction produced within a sessile water droplet by thermocavitation. The jets are driven by an acoustic shock wave emitted by the collapse of a hemispherical vapor bubble at the liquid-solid/substrate interface. The generated shock wave is reflected at the liquid-air interface due to acoustic impedance mismatch generating multiple reflections inside the droplet. During each reflection, a force is exerted on the interface driving the jets. Depending on the position of the generation of the bubble within the droplet, the mechanical energy of the shock wave is focused on different regions at the liquid-air interface, ejecting cylindrical liquid jets at different angles. The ejected jet angle dependence is explained by a simple ray tracing model of the propagation of the acoustic shock wave inside the droplet.

13.
Cell Tissue Bank ; 18(2): 271-280, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28255773

RESUMO

Establishment of continuous cell lines from human normal and tumor tissues is an extended and useful methodology for molecular characterization of cancer pathophysiology and drug development in research laboratories. The exchange of these cell lines between different labs is a common practice that can compromise assays reliability due to contamination with microorganism such as mycoplasma or cells from different flasks that compromise experiment reproducibility and reliability. Great proportions of cell lines are contaminated with mycoplasma and/or are replaced by cells derived for a different origin during processing or distribution process. The scientific community has underestimated this problem and thousand of research experiment has been done with cell lines that are incorrectly identified and wrong scientific conclusions have been published. Regular contamination and authentication tests are necessary in order to avoid negative consequences of widespread misidentified and contaminated cell lines. Cell banks generate, store and distribute cell lines for research, being mandatory a consistent and continuous quality program. Methods implementation for guaranteeing both, the absence of mycoplasma and authentication in the supplied cell lines, has been performed in the Andalusian Health System Biobank. Specifically, precise results were obtained using real time PCR detection for mycoplasma and 10 STRs identification by capillary electrophoresis for cell line authentication. Advantages and disadvantages of these protocols are discussed.


Assuntos
Bancos de Espécimes Biológicos , Técnicas de Cultura de Células/métodos , Linhagem Celular/microbiologia , DNA Bacteriano/isolamento & purificação , Mycoplasma/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , DNA Bacteriano/genética , Humanos , Mycoplasma/genética , Infecções por Mycoplasma/microbiologia , Controle de Qualidade
14.
J Food Sci Technol ; 54(10): 3192-3200, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28974804

RESUMO

In the present study total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity and antimicrobial properties of grape (Vitis vinifera var. Red Globe) stem extract is reported. Also, the identification of main phenolic compounds was carried out by UPLC-PAD analysis. TPC and TFC of extract were 37.25 g GAE kg-1 and 98.07 g QE kg-1, respectively. Extract showed an antioxidant capacity of 132.60 and 317 g TE kg-1 for DPPH and ABTS radical scavenging capacity, respectively. The main phenolic compounds identified were rutin, gallic acid, chlorogenic acid, caffeic acid, catechin and ferulic acid. Extract inhibited the growth of Listeria monocytogenes, Staphylococcus aureus, Salmonella enterica subsp. enterica serovar Typhimurium, and Escherichia coli O157: H7 at MIC range 16-18 g L-1. Extract affected the different phases of bacterial growth. In addition, application of Extract (25 g L-1) as a sanitizer was effective to reduce the populations of all bacteria inoculated in lettuce (0.859-1.884 log reduction) and spinach (0.843-2.605 log reduction). This study emphasizes the potential of grape processing byproducts as an emergent and attractive source of bioactive compounds with antioxidant properties and antimicrobial activity against important foodborne pathogens. The study demonstrated that stem extract could be used to control the presence of human pathogenic bacteria in fresh leafy vegetables.

15.
Crit Rev Food Sci Nutr ; 56(10): 1717-27, 2016 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-25763467

RESUMO

Food consumers and industries urged the need of natural alternatives to assure food safety and quality. As a response, the use of natural compounds from herbs and spices is an alternative to synthetic additives associated with toxic problems. This review discusses the antimicrobial and antioxidant activity of oregano essential oil (OEO) and its potential as a food additive. Oregano is a plant that has been used as a food seasoning since ancient times. The common name of oregano is given to several species: Origanum (family: Lamiaceae) and Lippia (family: Verbenaceae), amongst others. The main compounds identified in the different OEOs are carvacrol and thymol, which are responsible for the characteristic odor, antimicrobial, and antioxidant activity; however, their content may vary according to the species, harvesting season, and geographical sources. These substances as antibacterial agents make the cell membrane permeable due to its impregnation in the hydrophobic domains, this effect is higher against gram positive bacteria. In addition, the OEO has antioxidant properties effective in retarding the process of lipid peroxidation in fatty foods, and scavenging free radicals. In this perspective, the present review analyzes and discusses the state of the art about the actual and potential uses of OEO as an antimicrobial and antioxidant food additives.


Assuntos
Anti-Infecciosos/análise , Antioxidantes/análise , Óleos Voláteis/análise , Origanum/química , Óleos de Plantas/análise , Aditivos Alimentares/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Conservação de Alimentos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Odorantes/análise , Paladar
16.
J Clin Densitom ; 19(4): 444-449, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27574779

RESUMO

The purpose of this study was to evaluate the frequency of osteoporosis (OP) in patients with Gaucher disease (GD) in Argentina. GD patients from 28 centers were consecutively included from April 2012 to 2014. Bone mineral density (BMD) was determined by dual X-ray absorptiometry in the lumbar spine and the femoral neck or the total proximal femur for patients ≥20 yr of age, and by whole-body scan in the lumbar spine in patients <20 yr of age. In children, mineral density was calculated using the chronological age and Z height. OP diagnosis was determined following adult and pediatric official position of the International Society for Clinical Densitometry. A total of 116 patients were included, of which 62 (53.5%) were women. The median age was 25.8 yr. All patients received enzyme replacement therapy, with a median time of 9.4 yr. Normal BMD was found in 89 patients (76.7%), whereas low bone mass (LBM) or osteopenia was found in 15 patients (13%) and OP in 12 patients (10.3%). The analysis of the pediatric population revealed that 4 patients (9.3%) had LBM and 3 (7%) had OP (Z-score ≤ -2 + fractures height-adjusted by Z), whereas in the adult population (n = 73), 11 patients (15%) had LBM or osteopenia and 9 (12.3%) had OP. Bone marrow infiltration and the presence of fractures were significantly correlated with the presence of OP (p = 0.04 and <0.001, respectively). This is the first study in Argentina and in the region describing the frequency of OP or LBM in GD patients treated with imiglucerase using the official position of the International Society for Clinical Densitometry.


Assuntos
Absorciometria de Fóton , Doença de Gaucher/complicações , Osteoporose/complicações , Osteoporose/diagnóstico por imagem , Absorciometria de Fóton/métodos , Adolescente , Adulto , Idoso , Argentina/epidemiologia , Densidade Óssea , Doenças Ósseas Metabólicas/complicações , Doenças Ósseas Metabólicas/diagnóstico por imagem , Doenças Ósseas Metabólicas/epidemiologia , Criança , Feminino , Colo do Fêmur/diagnóstico por imagem , Doença de Gaucher/epidemiologia , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Adulto Jovem
17.
Phys Rev Lett ; 113(24): 240501, 2014 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-25541759

RESUMO

When an initially entangled pair of qubits undergoes local decoherence processes, there are a number of ways in which the original entanglement can spread throughout the multipartite system consisting of the two qubits and their environments. Here, we report theoretical and experimental results regarding the dynamics of the distribution of entanglement in this system. The experiment employs an all optical setup in which the qubits are encoded in the polarization degrees of freedom of two photons, and each local decoherence channel is implemented with an interferometer that couples the polarization to the path of each photon, which acts as an environment. We monitor the dynamics and distribution of entanglement and observe the transition from bipartite to multipartite entanglement and back, and show how these transitions are intimately related to the sudden death and sudden birth of entanglement. The multipartite entanglement is further analyzed in terms of three- and four-partite entanglement contributions, and genuine four-qubit entanglement is observed at some points of the evolution.

18.
Phys Rev Lett ; 112(16): 160501, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24815628

RESUMO

A measurement-based quantum computer could consist of a local-gapped Hamiltonian system, whose thermal states-at sufficiently low temperature-are universal resources for the computation. Initialization of the computer would correspond to cooling the system. We perform an experimental quantum simulation of such a cooling process with entangled photons. We prepare three-qubit thermal cluster states exploiting the equivalence between local dephasing and thermalization for these states. This allows us to tune the system's temperature by changing the dephasing strength. We monitor the entanglement as the system cools down and observe the transitions from separability to bound entanglement, and then to free entanglement. We also analyze the performance of the system for measurement-based single-qubit state preparation. These studies constitute a basic characterization of experimental cluster-state computation under imperfect conditions.

19.
Genet Mol Res ; 13(2): 3850-8, 2014 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-24938473

RESUMO

Phenylalanine ammonia lyase (PAL) and p-coumarate 3-hydroxylase (C3H) are key enzymes in the phenylpropanoid pathway. The relative expression of PAL and C3H was evaluated in mango fruit cultivar 'Ataulfo' in four ripening stages (RS1, RS2, RS3, and RS4) by quantitative polymerase chain reaction. In addition, enzyme activity of PAL and C3H was determined in mango fruits during ripening. The PAL levels were downregulated at the RS2 and RS3 stages, while C3H levels were upregulated in fruits only at RS3. The enzyme activity of PAL followed a pattern that was different from that of the PAL expression, thus suggesting regulation at several levels. For C3H, a regulation at the transcriptional level is suggested because a similar pattern was revealed by its activity and transcript level. In this study, the complexity of secondary metabolite biosynthesis regulation is emphasized because PAL and C3H enzymes are involved in the biosynthesis of several secondary metabolites that are active during all mango ripening stages.


Assuntos
Frutas/crescimento & desenvolvimento , Mangifera/genética , Oxigenases de Função Mista/biossíntese , Fenilalanina Amônia-Liase/biossíntese , Clonagem Molecular , Frutas/genética , Regulação da Expressão Gênica de Plantas , Mangifera/crescimento & desenvolvimento , Oxigenases de Função Mista/genética , Fenilalanina Amônia-Liase/genética , Reação em Cadeia da Polimerase
20.
MicroPubl Biol ; 20242024.
Artigo em Inglês | MEDLINE | ID: mdl-38304163

RESUMO

To facilitate cell identification for expression pattern analysis in C. elegans , an SL2::GFP::H2B fluorescent reporter cassette has become a popular and widely used choice to generate nuclear localized reporter alleles by CRISPR/Cas9 genome engineering. When added at the 3' end of a locus of interest, this cassette concentrates GFP into the nucleus and permits the identification of expressing cells, for example with the help of the NeuroPAL tool. However, there are instances in which it is desirable to visualize the complete morphology of a cell that expresses an SL2::GFP::H2B reporter cassette. We describe here a CRISPR/Cas9-engineering strategy to transform an endogenous SL2::GFP::H2B tag into a cytosolic tag by insertion of the self-cleaving T2A tag in between GFP and H2B.

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