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Lila Simakachorn Pornthep Tanpowpong Suwanee Chanprasertyothin Supranee Thongpradit Suporn Treepongkaruna 《The Turkish journal of gastroenterology》2021,32(1):70
Background/Aims: Prolonged acid suppression from proton pump inhibitor (PPI) has been shown to cause gut microbiota alteration, which may increase the risk of various infections in adults. We aimed to characterize gut microbiota profiles in children after a short-term use of PPI.Materials and Methods: Children aged 1-18 years who underwent PPI therapy were included during April-December 2017. We excluded children who previously used antibiotics or acid suppressants and who had a history of acute gastroenteritis or specific food avoidance one month prior to the enrolment. The stool samples before and after the PPI use were collected for gut microbiota composition. The 16S ribosomal RNA gene sequencing was performed by using Illumina MiSeq. The differences in the gut microbiota profile after the use of PPI were compared to pre-PPI period.Results: We completed stool collection in 20 children (median age of 5.8 years and 60% were female). No significant changes in the overall number of species-level taxonomy categories or predominant bacteria belonging to the phylum (Bacteroidetes) were noted. We found a trend increase in the proportion of the phylum Firmicutes among children living in the designated metropolitan/suburban area (P = .07) and among males (P = .11). In four children with infection-related adverse effects, we noted a nonsignificant increase in the proportion of the phylum Firmicutes after the PPI use (from 35% to 52%, P = .14).Conclusions: Even the total number of and predominant gut microbiota did not significantly change after a four- to eight-week course of PPI therapy; we found a trend of increase in the proportion of the phylum Firmicutes in certain groups of children. 相似文献
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Jaime Tamez-Salazar Teresa Mireles-Aguilar Cynthia de la Garza-Ramos Marisol Garcia-Garcia Ana S. Ferrigno Alejandra Platas Cynthia Villarreal-Garza 《The oncologist》2020,25(12):1047-1054
IntroductionIn Mexico, there are considerable health system delays in the diagnosis and treatment initiation of women with breast cancer. Alerta Rosa is a navigation program in Nuevo Leon that aims to reduce barriers that impede the timely management of these patients.Patients and MethodsSince December 2017, women who registered to receive medical evaluations by Alerta Rosa were stratified based on their clinical characteristics into three priority groups (“Red,” “Yellow,” and “Green”). According to the category assigned, patients were scheduled imaging studies and medical appointments with breast specialists on a preferential basis.ResultsUp until December 2019, 561 patients were scheduled for medical evaluations. Of them, 59% were classified as “Red,” 25% “Yellow,” and 16% “Green” priority. The median time from stratification to first medical evaluation was 4, 6, and 7 days, respectively (p = .003). Excluding those who had a prior breast cancer diagnosis, 21 patients were diagnosed by Alerta Rosa, with the initial “Red” priority classification demonstrating a sensitivity of 95% (95% confidence interval [CI], 75.1%–99.9%) and specificity of 42% (95% CI, 37.1%–47.1%) for breast cancer. The median time elapsed from initial patient contact to diagnosis and treatment initiation was 16 days and 39 days, respectively. The majority (72%) of patients were diagnosed at an early stage (0–II).ConclusionThis patient prioritization system adequately identified women with different probabilities of having breast cancer. Efforts to replicate similar triage systems in resource‐constrained settings where screening programs are ineffective could prove to be beneficial in reducing diagnostic intervals and achieving early‐stage diagnoses.Implications for PracticeLow‐ and middle‐income countries such as Mexico currently lack the infrastructure to achieve effective breast cancer screening and guarantee prompt access to health care when required. To reduce the disease burden in such settings, strategies targeting early detection are urgently needed. Patient navigation programs aid in the reduction of health system intervals and optimize the use of available resources. This article presents the introduction of a triage system based on initial patient concern. Appointment prioritization proved to be successful at reducing health system intervals and achieving early‐stage diagnoses by overcoming barriers that impede early access to quality medical care. 相似文献
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Jean-Pierre Bédos Bernard Allaouchiche Laurence Armand-Lefèvre Olivier Baldesi Lila Bouadma Dominique Decré Samy Figueiredo Rémy Gauzit Benoit Guery Nicolas Joram Boris Jung Sigismond Lasocki Alain Lepape Fabrice Lesage Olivier Pajot François Philippart Bertrand Souweine Pierre Tattevin Jean-François Timsit Jean-Ralph Zahar Cédric Bretonnière Marc Leone Christophe Milési Benoît Misset 《Réanimation》2014,23(5):558-582
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Mouzhe Xie Xiaofei Yu Lila V. H. Rodgers Daohong Xu Ignacio Chi-Durn Adrien Toros Niels Quack Nathalie P. de Leon Peter C. Maurer 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(8)
Quantum metrology enables some of the most precise measurements. In the life sciences, diamond-based quantum sensing has led to a new class of biophysical sensors and diagnostic devices that are being investigated as a platform for cancer screening and ultrasensitive immunoassays. However, a broader application in the life sciences based on nanoscale NMR spectroscopy has been hampered by the need to interface highly sensitive quantum bit (qubit) sensors with their biological targets. Here, we demonstrate an approach that combines quantum engineering with single-molecule biophysics to immobilize individual proteins and DNA molecules on the surface of a bulk diamond crystal that hosts coherent nitrogen vacancy qubit sensors. Our thin (sub–5 nm) functionalization architecture provides precise control over the biomolecule adsorption density and results in near-surface qubit coherence approaching 100 μs. The developed architecture remains chemically stable under physiological conditions for over 5 d, making our technique compatible with most biophysical and biomedical applications.Recent developments in quantum engineering and diamond processing have brought us considerably closer to performing nanoscale NMR and electron paramagnetic resonance (EPR) spectroscopy of small ensembles and even individual biomolecules. Notably, these advances have enabled the detection of the nuclear spin noise from a single ubiquitin protein (1) and the probing of the EPR spectrum of an individual paramagnetic spin label conjugated to a protein (2) or DNA molecule (3). More recently, lock-in detection and signal reconstruction techniques (4, 5) have enabled one- and multidimensional NMR spectroscopy with 0.5-Hz spectral resolution (6–8). More advanced control sequences at cryogenic temperatures have further enabled mapping the precise location of up to 27 13C nuclear spins inside of diamond (9). Yet biologically meaningful spectroscopy on intact biomolecules remains elusive. One of the main outstanding challenges, which is required to perform nanoscale magnetic resonance spectroscopy of biomolecules, is the need to immobilize the target molecules within the 10- to 30-nm sensing range (2, 3, 7) of a highly coherent nitrogen vacancy (NV) qubit sensor. Immobilization is necessary because an untethered molecule would otherwise diffuse out of the detection volume within a few tens of microseconds.Various avenues to the functionalization of high-quality, single-crystalline diamond chips have been pursued over the last decade (10–12). However, none of the currently known approaches has led to the desired results of interfacing a coherent quantum sensor with target biomolecules. For example, hydrogen-terminated diamond surfaces can be chemically modified and form biologically stable surfaces (10, 13); but near-surface NV centers are generally charge-unstable under hydrogen termination (14), posing open challenges for NV sensing. On the other hand, oxygen-terminated diamond surfaces have been used to create charge stable NV– centers with exceptional coherence times within 10 nm from the diamond surface (15). However, perfectly arranged, ether-terminated diamond surfaces generally lack chemically functionalizable surface groups (such as carboxyl or hydroxyl groups), making it difficult to control immobilization density and surface passivation. Other platforms such as diamond nanocrystals can generally be functionalized (16, 17) because of their heterogeneous surface chemistry, but they do not possess the coherence times needed for nanoscale magnetic resonance spectroscopy. Our approach (Fig. 1A) overcomes these limitations by utilizing a 2-nm-thick Al2O3 layer deposited onto an oxygen-terminated diamond surface by atomic layer deposition (ALD). This Al2O3 “adhesion” layer is silanized by N-[3-(trimethoxysilyl)propyl]ethylenediamine to create an amine (–NH2) -terminated surface, which in turn is then grafted with a monolayer of heterobifunctional polyethylene glycol (PEG) via an N-hydroxysuccinimide (NHS) reaction, a process also referred as PEGylation. The PEG layer serves two purposes. First, it passivates the diamond surface to prevent nonspecific adsorption of biomolecules. Second, by adjusting the density of PEG molecules with functional groups (e.g., biotin or azide), we can control the immobilization density of proteins or DNA target molecules on the diamond surface. Furthermore, the small persistence length of the PEG linker (∼0.35 nm) allows the immobilized biomolecules to undergo rotational diffusion (18). This tumbling motion is the basis for motional averaging of the NMR spectra and helps to prevent immobilization of molecules in biologically inactive orientations.Open in a separate windowFig. 1.Architecture and characterization of the diamond functionalization approach. (A) Schematic illustration of the functionalization process. A thin layer of Al2O3 (gray) was deposited to the pristine, oxygen-terminated diamond surfaces (blue), followed by silanization (purple) and PEGylation (green). Functional groups (biotin, yellow circle; azide, red triangle) allow for cross-linking with target biomolecules. AFM characterization of the surfaces (B) and XPS Al2p signal after each step of the functionalization (C). (D) Illustration of the overall chemical functionalization architecture (not to scale), with corresponding thicknesses. (E) Illustration of SPAAC reaction. (F) A lithographically fabricated Al2O3 pattern on the diamond surface by lift-off, with a thickness of ∼2.1 nm. The Al2O3 layer is uniform without the presence of pin holes. The elevated edges originate from lift-off combined with ALD deposition. 相似文献
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Nabila Brahmi-Chendouh Simona Piccolella Giuseppina Crescente Francesca Pacifico Lila Boulekbache Sabrina Hamri-Zeghichi Salah Akkal Khodir Madani Severina Pacifico 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2019,27(3):692-702
Nowadays, advanced extraction techniques and highly sensitive metabolic profiling methods are effectively employed to get new information on plant chemical constituents. Among them wild medicinal plants or their parts, with large and ancient use in folk medicine, are investigated for their potential functional use and cultivation. In this context, Inula viscosa leaves engaged our attention. A simple experimental design, based on Soxhlet extraction and chromatographic fractionation, allowed us to obtain the investigated polyphenol fraction (IvE). UHPLC-HRMS analyses revealed shikimoyl depsides of caffeic acid and unusual dihydrobenzofuran lignans as main secondary metabolites. These compounds, together with cinchonain-type phenols, and hydroxycinnamoyl flavonol glycosides, are reported for the first time in inula. Overall, forty-three secondary metabolites were identified. The extract exerted a remarkable antiradical activity towards DPPH• and ABTS+•. Furthermore, it was able to inhibit cell viability and mitochondrial redox activity of neuroblastoma, hepatoblastoma and colon carcinoma cells, whereas it did not affect cell density of HaCaT cells immortalized human keratinocytes. As detected by the oxidant-sensing probe 2′,7′-dichlorodihydrofluorescein diacetate, the inhibitory responses seemed to be related to IvE-induced increase of intracellular reactive oxygen species (ROS). The obtained results highlighted that inula leaves, nowadays even undervalued and unexplored, could be considered a renewable source of nutraceutical compounds. 相似文献
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Ana Claudia Pelissari Kravchychyn Raquel Munhoz da Silveira Campos Yasmin Alaby Martins Ferreira Sofia Emanuelle de Castro Ferreira Vicente Flvia Campos Corgosinho Lila Missae Oyama Valter Tadeu Boldarine Lian Tock David Thivel Ana Raimunda Dmaso 《Arquivos brasileiros de cardiologia》2022,118(1):33
BackgroundThe action of atrial natriuretic peptide (ANP) on natriuresis, diuresis and vasodilatation, insulin resistance, liver, kidney, and adipose tissue may contribute to the healthy metabolic and cardiovascular development. Even though the circulating level of ANP is reduced in patients with obesity, its response to weight loss remains poorly explored in pediatric populations.ObjectiveTo evaluate the effects of ANP variations in response to interdisciplinary weight loss intervention on metabolic syndrome (MetS) and cardiometabolic risks in adolescents with obesity.Methods73 adolescents with obesity attended a 20-week clinical interdisciplinary weight loss therapy including clinical, nutritional, psychological and exercise training approach. Body composition, biochemical analyses and blood pressure were evaluated. MetS was classified according to the International Diabetes Federation (IDF) (2007). After the treatment, volunteers were divided according to Increasing (n=31) or Decreasing (n=19) ANP plasma levels.ResultsBoth groups present significant reduction of body weight, Body Mass Index (BMI), waist, neck and hip circumferences (WC, NC and HC, respectively) and increasing fat-free mass (FFM). Interestingly, a significant reduction in body fat, TG/HDL-c ratio and MetS prevalence (from 23% to 6%) was observed in the Increased ANP group only.ConclusionThis study suggests that an increase in ANP serum levels after weight loss therapy could be associated with improvements in cardiometabolic risks and the reduced prevalence of MetS in adolescents with obesity. 相似文献
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