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1.
Proc Natl Acad Sci U S A ; 120(31): e2217033120, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37487063

RESUMEN

Type I spiral ganglion neurons (SGNs) are the auditory afferents that transmit sound information from cochlear inner hair cells (IHCs) to the brainstem. These afferents consist of physiological subtypes that differ in their spontaneous firing rate (SR), activation threshold, and dynamic range and have been described as low, medium, and high SR fibers. Lately, single-cell RNA sequencing experiments have revealed three molecularly defined type I SGN subtypes. The extent to which physiological type I SGN subtypes correspond to molecularly defined subtypes is unclear. To address this question, we have generated mouse lines expressing CreERT2 in SGN subtypes that allow for a physiological assessment of molecular subtypes. We show that Lypd1-CreERT2 expressing SGNs represent a well-defined group of neurons that preferentially innervate the IHC modiolar side and exhibit a narrow range of low SRs. In contrast, Calb2-CreERT2 expressing SGNs preferentially innervate the IHC pillar side and exhibit a wider range of SRs, thus suggesting that a strict stratification of all SGNs into three molecular subclasses is not obvious, at least not with the CreERT2 tools used here. Genetically marked neuronal subtypes refine their innervation specificity onto IHCs postnatally during the time when activity is required to refine their molecular phenotype. Type I SGNs thus consist of genetically defined subtypes with distinct physiological properties and innervation patterns. The molecular subtype-specific lines characterized here will provide important tools for investigating the role of the physiologically distinct type I SGNs in encoding sound signals.


Asunto(s)
Tronco Encefálico , Células Ciliadas Vestibulares , Animales , Ratones , Cóclea , Células Ciliadas Auditivas Internas , Neuronas
2.
Phys Chem Chem Phys ; 25(25): 16727-16734, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37161538

RESUMEN

Polymorphism and phase transitions in sodium diuranate, Na2U2O7, are investigated with density functional perturbation theory (DFPT). Thermal properties of crystalline α-, ß- and γ-Na2U2O7 polymorphs are predicted from DFPT phonon calculations, i.e., the first time for the high-temperature γ-Na2U2O7 phase (R3̄m symmetry). The standard molar isochoric heat capacities predicted within the quasi-harmonic approximation are for P21/a α-Na2U2O7 and C2/m ß-Na2U2O7, respectively. Gibbs free energy calculations reveal that α-Na2U2O7 (P21/a) and ß-Na2U2O7 (C2/m) are almost energetically degenerate at low temperature, with ß-Na2U2O7 becoming slightly more stable than α-Na2U2O7 as temperature increases. These findings are consistent with XRD data showing a mixture of α and ß phases after cooling of γ-Na2U2O7 to room temperature and the observation of a sluggish α → ß phase transition above ca. 600 K. A recently observed α-Na2U2O7 structure with P21 symmetry is also shown to be metastable at low temperature. Based on Gibbs free energy, no direct ß â†’ γ solid-solid phase transition is predicted at high temperature, although some experiments reported the existence of such phase transition around 1348 K. This, along with recent experiments, suggests the occurrence of a multi-step process consisting of initial ß-phase decomposition, followed by recrystallization into γ-phase as temperature increases.

3.
Plant J ; 108(2): 378-393, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34312931

RESUMEN

Despite being of vital importance for seed establishment and grain quality, starch degradation remains poorly understood in organs such as cereal or legume seeds. In cereals, starch degradation requires the synergetic action of different isoforms of α-amylases. Ubiquitous overexpression of TaAmy2 resulted in a 2.0-437.6-fold increase of total α-amylase activity in developing leaf and harvested grains. These increases led to dramatic alterations of starch visco-properties and augmentation of soluble carbohydrate levels (mainly sucrose and α-gluco-oligosaccharide) in grain. Interestingly, the overexpression of TaAMY2 led to an absence of dormancy in ripened grain due to abscisic acid (ABA) insensitivity. Using an allosteric α-amylase inhibitor (acarbose), we demonstrated that ABA insensitivity was due to the increased soluble carbohydrate generated by the α-amylase excess. Independent from the TaAMY2 overexpression, inhibition of α-amylase during germination led to the accumulation of soluble α-gluco-oligosaccharides without affecting the first stage of germination. These findings support the hypotheses that (i) endosperm sugar may overcome ABA signalling and promote sprouting, and (ii) α-amylase may not be required for the initial stage of grain germination, an observation that questions the function of the amylolytic enzyme in the starch degradation process during germination.


Asunto(s)
Germinación/fisiología , Semillas/metabolismo , Almidón/metabolismo , Triticum/metabolismo , alfa-Amilasas/genética , Ácido Abscísico/farmacología , Regulación de la Expresión Génica de las Plantas , Latencia en las Plantas/efectos de los fármacos , Latencia en las Plantas/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Semillas/genética , Semillas/crecimiento & desarrollo , Almidón/química , Almidón/genética , Azúcares/metabolismo , Triticum/genética , alfa-Amilasas/metabolismo
4.
Am J Physiol Lung Cell Mol Physiol ; 321(1): L91-L101, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-33908264

RESUMEN

During agonist stimulation of airway smooth muscle (ASM), agonists such as ACh induce a transient increase in cytosolic Ca2+ concentration ([Ca2+]cyt), which leads to a contractile response [excitation-contraction (E-C) coupling]. Previously, the sensitivity of the contractile response of ASM to elevated [Ca2+]cyt (Ca2+ sensitivity) was assessed as the ratio of maximum force to maximum [Ca2+]cyt. However, this static assessment of Ca2+ sensitivity overlooks the dynamic nature of E-C coupling in ASM. In this study, we simultaneously measured [Ca2+]cyt and isometric force responses to three concentrations of ACh (1, 2.6, and 10 µM). Both maximum [Ca2+]cyt and maximum force responses were ACh concentration dependent, but force increased disproportionately, thereby increasing static Ca2+ sensitivity. The dynamic properties of E-C coupling were assessed in several ways. The temporal delay between the onset of ACh-induced [Ca2+]cyt and onset force responses was not affected by ACh concentration. The rates of rise of the ACh-induced [Ca2+]cyt and force responses increased with increasing ACh concentration. The integral of the phase-loop plot of [Ca2+]cyt and force from onset to steady state also increased with increasing ACh concentration, whereas the rate of relaxation remained unchanged. Although these results suggest an ACh concentration-dependent increase in the rate of cross-bridge recruitment and in the rate of rise of [Ca2+]cyt, the extent of regulatory myosin light-chain (rMLC20) phosphorylation was not dependent on ACh concentration. We conclude that the dynamic properties of [Ca2+]cyt and force responses in ASM are dependent on ACh concentration but reflect more than changes in the extent of rMLC20 phosphorylation.


Asunto(s)
Calcio/metabolismo , Colinérgicos/farmacología , Citosol/metabolismo , Contracción Muscular , Músculo Liso/metabolismo , Sistema Respiratorio/metabolismo , Animales , Citosol/efectos de los fármacos , Femenino , Masculino , Músculo Liso/efectos de los fármacos , Sistema Respiratorio/efectos de los fármacos , Porcinos
5.
J Clin Immunol ; 41(1): 136-146, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33090292

RESUMEN

Patients with rare homozygous mutations in signal transducer and activator of transcription 5B (STAT5B) develop immunodeficiency resulting in chronic eczema, chronic infections, autoimmunity, and chronic lung disease. STAT5B-deficient patients are typically diagnosed in the teenage years, limiting our understanding of the development of associated phenotypic immune abnormalities. We report the first detailed chronological account of post-natal immune dysfunction associated with STAT5B deficiency in humans. Annual immunophenotyping of three siblings carrying a novel homozygous nonsense mutation in STAT5B was carried out over 4 years between the ages of 7 months to 8 years. All three siblings demonstrated consistent B cell hyperactivity including elevated IgE levels and autoantibody production, associated with diagnoses of atopy and autoimmunity. Total T cell levels in each sibling remained normal, with regulatory T cells decreasing in the oldest sibling. Interestingly, a skewing toward memory T cells was identified, with the greatest changes in CD8+ effector memory T cells. These results suggest an importance of STAT5B in B cell function and naïve versus memory T cell survival. Progressive dysregulation of FOXP3+ regulatory T cells and CD8+ memory T cell subsets reveal a crucial role of STAT5B in T cell homeostasis. The early diagnosis and focused immune evaluations of these three young STAT5B-deficient siblings support an important role of STAT5B in adaptive immune development and function.


Asunto(s)
Inmunidad Adaptativa/genética , Síndromes de Inmunodeficiencia/diagnóstico , Síndromes de Inmunodeficiencia/genética , Factor de Transcripción STAT5/deficiencia , Hermanos , Autoinmunidad , Linfocitos B/inmunología , Linfocitos B/metabolismo , Biomarcadores , Línea Celular , Consanguinidad , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Estudios de Asociación Genética , Homocigoto , Humanos , Lactante , Masculino , Células T de Memoria/inmunología , Células T de Memoria/metabolismo , Mutación , Fenotipo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Secuenciación del Exoma
6.
Rev Endocr Metab Disord ; 22(1): 91-99, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33025383

RESUMEN

The continuum of growth hormone (GH)-IGF-I axis defects extends from severe to mild GH deficiency, through short stature disorders of undefined aetiology, to GH insensitivity disorders which can also be mild or severe. This group of defects comprises a spectrum of endocrine, biochemical, phenotypic and genetic abnormalities. The extreme cases are generally easily diagnosed because they conform to well-studied phenotypes with recognised biochemical features. The milder cases of both GH deficiency and GH insensitivity are less well defined and also overlap with the group of short stature conditions, labelled as idiopathic short stature (ISS). In this review the continuum model, which plots GH sensitivity against GH secretion, will be discussed. Defects causing GH deficiency and GH insensitivity will be described, together with the use of a diagnostic algorithm, designed to aid investigation and categorisation of these defects. The continuum will also be discussed in the context of growth-promoting endocrine therapy.


Asunto(s)
Trastornos del Crecimiento , Hormona de Crecimiento Humana , Trastornos del Crecimiento/diagnóstico , Hormona de Crecimiento Humana/deficiencia , Humanos , Factor I del Crecimiento Similar a la Insulina
7.
Environ Sci Technol ; 55(5): 3270-3282, 2021 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-33566597

RESUMEN

Microbial communities are believed to outperform monocultures in the complete catabolism of organic pollutants via reduced metabolic burden and increased robustness to environmental challenges; however, the interaction mechanism in functional microbiomes remains poorly understood. Here, three functionally differentiated activated sludge microbiomes (S1: complete catabolism of sulfamethoxazole (SMX); S2: complete catabolism of the phenyl part of SMX ([phenyl]-SMX) with stable accumulation of its heterocyclic product 3-amino-5-methylisoxazole (3A5MI); A: complete catabolism of 3A5MI rather than [phenyl]-SMX) were enriched. Combining time-series cultivation-independent microbial community analysis, DNA-stable isotope probing, molecular ecological network analysis, and cultivation-dependent function verification, we identified key players involved in the SMX degradation process. Paenarthrobacter and Nocardioides were primary degraders for the initial cleavage of the sulfonamide functional group (-C-S-N- bond) and 3A5MI degradation, respectively. Complete catabolism of SMX was achieved by their cross-feeding. The co-culture of Nocardioides, Acidovorax, and Sphingobium demonstrated that the nondegraders Acidovorax and Sphingobium were involved in the enhancement of 3A5MI degradation. Moreover, we unraveled the internal labor division patterns and connections among the active members centered on the two primary degraders. Overall, the proposed methodology is promisingly applicable and would help generate mechanistic, predictive, and operational understanding of the collaborative biodegradation of various contaminants. This study provides useful information for synthetic activated sludge microbiomes with optimized environmental functions.


Asunto(s)
Microbiota , Contaminantes Químicos del Agua , Antibacterianos , Biodegradación Ambiental , Interacciones Microbianas , Aguas del Alcantarillado , Sulfametoxazol
8.
Phys Chem Chem Phys ; 23(12): 7088-7100, 2021 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-33876075

RESUMEN

Studying the structural environment of the VIV ions doped in the metal-organic framework (MOF) DUT-5(Al) ((AlIIIOH)BPDC) with electron paramagnetic resonance (EPR) reveals four different vanadium-related spectral components. The spin-Hamiltonian parameters are derived by analysis of X-, Q- and W-band powder EPR spectra. Complementary Q-band Electron Nuclear DOuble Resonance (ENDOR) experiments, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray spectroscopy (EDX), X-Ray Diffraction (XRD) and Fourier Transform InfraRed (FTIR) measurements are performed to investigate the origin of these spectral components. Two spectral components with well resolved 51V hyperfine structure are visible, one corresponding to VIV[double bond, length as m-dash]O substitution in a large (or open) pore and one to a narrow (or closed) pore variant of this MOF. Furthermore, a broad structureless Lorentzian line assigned to interacting vanadyl centers in each other's close neighborhood grows with increasing V-concentration. The last spectral component is best visible at low V-concentrations. We tentatively attribute it to (VIV[double bond, length as m-dash]O)2+ linked with DMF or dimethylamine in the pores of the MOF. Simulations using these four spectral components convincingly reproduce the experimental spectra and allow to estimate the contribution of each vanadyl species as a function of V-concentration.

9.
Pediatr Cardiol ; 42(3): 481-491, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33242100

RESUMEN

Vasculopathy has been identified in young individuals with Turner syndrome (TS). No studies in young individuals with TS have investigated whether this vasculopathy progresses over time. The objective of this study is to describe the changes in vasculopathy over time in a cohort of young individuals with TS. Repeat ultrasound and SphygmoCor CPV® (AtCor Medical) measurements of carotid thickness and peripheral arterial stiffness were performed. Vascular measurements were compared at baseline and follow-up. Follow-up measurements were also compared to historical lean (L) and obese (O) age-, race-, and sex-matched non-TS controls. Thirty-five individuals with TS were studied at a mean age of 19.4 years (range, 13.9-27.5). Mean time to follow-up was 7.2 years (range, 7.1-7.8). Carotid intima media thickness increased by 0.03 ± 0.07 mm (p < 0.01) over time, but was less than L and O controls at follow-up. Pulse wave velocity carotid-femoral increased by 0.51 ± 0.86 m/s (p < 0.01) over time, but was similar to L and less than O controls at follow-up. Augmentation index (AIx) remained unchanged (p = 0.09) over time, but was significantly higher at follow-up than both control groups (p < 0.01 for both). There were no identified differences between 45,X and other TS genotypes. We demonstrate evidence of vascular thickening and stiffening over 7 years in a cohort of young individuals with TS, as well as a persistently increased augmentation index compared to L and O non-TS controls. It is unclear whether the increase in vascular structure and function are related to normal aging or if TS is a risk factor. Higher body mass index seems to be a risk factor. Early estrogen replacement and longer exposure to growth hormone therapy need to be further explored as potential protective factors.


Asunto(s)
Síndrome de Turner/complicaciones , Enfermedades Vasculares/etiología , Enfermedades Vasculares/fisiopatología , Adolescente , Adulto , Índice de Masa Corporal , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/fisiopatología , Grosor Intima-Media Carotídeo , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Humanos , Hipertensión/epidemiología , Masculino , Obesidad/complicaciones , Análisis de la Onda del Pulso , Factores de Riesgo , Ultrasonografía/métodos , Enfermedades Vasculares/diagnóstico por imagen , Rigidez Vascular , Adulto Joven
10.
Environ Microbiol ; 22(7): 2463-2468, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32286010

RESUMEN

There are a multitude of resistance strategies that microbes can apply to avoid inhibition by antimicrobials. One of these strategies is the enzymatic modification of the antibiotic, in a process generally termed inactivation. Furthermore, some microorganisms may not be limited to the mere inactivation of the antimicrobial compounds. They can continue by further enzymatic degradation of the compounds' carbon backbone, taking nutritional and energetic advantage of the former antibiotic. This driving force to harness an additional food source in a complex environment adds another level of complexity to the reasonably well-understood process of antibiotic resistance proliferation on a single cell level: It brings bioprotection into play at the level of microbial community. Despite the possible implications of a resistant community in a host and a lurking antibiotic failure, knowledge of degradation pathways of antibiotics and their connections is scarce. Currently, it is limited to only a few families of antibiotics (e.g. ß-lactams and sulfonamides). In this article, we discuss the fluctuating nature of the relationship between antibiotic resistance and the biodegradation of antibiotics. This distinction mainly depends on the genetic background of the microbe, as general resistance genes can be recruited to function in a biodegradation pathway.


Asunto(s)
Antibacterianos/metabolismo , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Farmacorresistencia Bacteriana/fisiología , Biodegradación Ambiental , Humanos , Sulfonamidas/metabolismo , Sulfonamidas/farmacología , beta-Lactamas/metabolismo , beta-Lactamas/farmacología
11.
Appl Environ Microbiol ; 86(4)2020 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-31811031

RESUMEN

Microorganisms in wastewater treatment plants (WWTPs) play a key role in the removal of pollutants from municipal and industrial wastewaters. A recent study estimated that activated sludge from global municipal WWTPs harbors 1 × 109 to 2 × 109 microbial species, the majority of which have not yet been cultivated, and 28 core taxa were identified as "most-wanted" ones (L. Wu, D. Ning, B. Zhang, Y. Li, et al., Nat Microbiol 4:1183-1195, 2019, https://doi.org/10.1038/s41564-019-0426-5). Cultivation and characterization of the "most-wanted" core bacteria are critical to understand their genetic, physiological, phylogenetic, and ecological traits, as well as to improve the performance of WWTPs. In this study, we isolated a bacterial strain, designated SJ-1, that represents a novel cluster within Betaproteobacteria and corresponds to OTU_16 within the 28 core taxa in the "most-wanted" list. Strain SJ-1 was identified and nominated as Casimicrobium huifangae gen. nov., sp. nov., of a novel family, Casimicrobiaceae. C. huifangae is ubiquitously distributed and is metabolically versatile. In addition to mineralizing various carbon sources (including carbohydrates, aromatic compounds, and short-chain fatty acids), C. huifangae is capable of nitrate reduction and phosphorus accumulation. The population of C. huifangae accounted for more than 1% of the bacterial population of the activated sludge microbiome from the Qinghe WWTP, which showed seasonal dynamic changes. Cooccurrence analysis suggested that C. huifangae was an important module hub in the bacterial network of Qinghe WWTP.IMPORTANCE The activated sludge process is the most widely applied biotechnology and is one of the best ecosystems to address microbial ecological principles. Yet, the cultivation of core bacteria and the exploration of their physiology and ecology are limited. In this study, the core and novel bacterial taxon C. huifangae was cultivated and characterized. This study revealed that C. huifangae functioned as an important module hub in the activated sludge microbiome, and it potentially plays an important role in municipal wastewater treatment plants.


Asunto(s)
Betaproteobacteria/clasificación , Betaproteobacteria/fisiología , Aguas del Alcantarillado/microbiología , Betaproteobacteria/genética , Microbiota , Filogenia , ARN Bacteriano/análisis , ARN Ribosómico 16S/análisis
12.
Phys Rev Lett ; 125(3): 033001, 2020 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-32745429

RESUMEN

Laser excitation and x-ray spectroscopy are combined to settle a long-standing question in persistent luminescence. A reversible electron transfer is demonstrated, controlled by light and showing the same kinetics as the persistent luminescence. Exposure to violet light induces charging by oxidation of the excited Eu^{2+} while Dy^{3+} is simultaneously reduced. Oppositely, detrapping of Dy^{2+} occurs at ambient temperature or by infrared illumination, yielding afterglow or optically stimulated luminescence, respectively.

13.
Muscle Nerve ; 61(5): 623-631, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32108355

RESUMEN

INTRODUCTION: Recombinant human insulin-like growth factor-1 (rhIGF-1) is a growth factor and has anabolic effects on muscle. We investigated whether rhIGF-1 therapy: 1) improves or preserves muscle function; and 2) improves growth in boys with Duchenne muscular dystrophy (DMD). METHODS: In this study we compared prepubescent, ambulatory, glucocorticoid-treated boys with DMD (n = 17) vs controls (glucocorticoid therapy only, n = 21) in a 6-month-long, prospective, randomized, controlled trial of subcutaneous rhIGF-1 therapy. The primary outcome was 6-minute walk distance (6MWD). Secondary outcomes included height velocity (HV), change in height standard deviation score (ΔHtSDS), motor function, cardiopulmonary function, body composition, insulin sensitivity, quality of life, and safety. RESULTS: Change in 6MWD was similar between groups (rhIGF-1 vs controls [mean ± SD]: 3.4 ± 32.4 vs -5.1 ± 50.2 meters, P = .53). Treated subjects grew more than controls (HV: 6.5 ± 1.7 vs 3.3 ± 1.3 cm/year, P < .0001; 6-month ΔHtSDS: 0.25, P < .0001). Lean mass and insulin sensitivity increased in treated subjects. DISCUSSION: In boys with DMD, 6 months of rhIGF-1 therapy did not change motor function, but it improved linear growth.


Asunto(s)
Estatura , Sustancias de Crecimiento/uso terapéutico , Resistencia a la Insulina , Factor I del Crecimiento Similar a la Insulina/uso terapéutico , Fuerza Muscular , Distrofia Muscular de Duchenne/tratamiento farmacológico , Proteínas Recombinantes/uso terapéutico , Absorciometría de Fotón , Glucemia/metabolismo , Automonitorización de la Glucosa Sanguínea , Composición Corporal , Niño , Quimioterapia Combinada , Glucocorticoides/uso terapéutico , Humanos , Imagen por Resonancia Magnética , Masculino , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/fisiopatología , Calidad de Vida , Resultado del Tratamiento , Prueba de Paso
14.
Inorg Chem ; 59(24): 18407-18419, 2020 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-33296192

RESUMEN

The synthesis, structure, and thermal stability of the periodate double perovskites A2NaIO6 (A= Ba, Sr, Ca) were investigated in the context of potential application for the immobilization of radioiodine. A combination of X-ray diffraction and neutron diffraction, Raman spectroscopy, and DFT simulations were applied to determine accurate crystal structures of these compounds and understand their relative stability. The compounds were found to exhibit rock-salt ordering of Na and I on the perovskite B-site; Ba2NaIO6 was found to adopt the Fm-3m aristotype structure, whereas Sr2NaIO6 and Ca2NaIO6 adopt the P21/n hettotype structure, characterized by cooperative octahedral tilting. DFT simulations determined the Fm-3m and P21/n structures of Ba2NaIO6 to be energetically degenerate at room temperature, whereas diffraction and spectroscopy data evidence only the presence of the Fm-3m phase at room temperature, which may imply an incipient phase transition for this compound. The periodate double perovskites were found to exhibit remarkable thermal stability, with Ba2NaIO6 only decomposing above 1050 °C in air, which is apparently the highest recorded decomposition temperature so far recorded for any iodine bearing compound. As such, these compounds offer some potential for application in the immobilization of iodine-129, from nuclear fuel reprocessing, with an iodine incorporation rate of 25-40 wt%. The synthesis of these compounds, elaborated here, is also compatible with both current conventional and future advanced processes for iodine recovery from the dissolver off-gas.

15.
Environ Sci Technol ; 54(5): 2821-2831, 2020 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-32013402

RESUMEN

Plastics waste and microplastics including polyethylene (PE) and polystyrene (PS) have been an environmental concern for years. Recent research has revealed that larvae of Galleria mellonella are capable of biodegrading low density PE film. In this study, we tested the feasibility of enhancing larval survival and the effect of supplementing the co-diet on plastic degradation by feeding the larvae beeswax or wheat bran as a co-diet. Significant mass loss of plastic was observed over a 21-day period, i.e., with respective consumption of 0.88 and 1.95 g by 150 larvae fed only either PS or PE. The formation of C═O and C-O containing functional groups and long chain fatty acids as the metabolic intermediates of plastics in the residual polymers indicated depolymerization and biodegradation. Supplementing beeswax and bran increased the survival rates but decreased the consumption of plastic. The changes in the gut microbiome revealed that Bacillus and Serratia were significantly associated with the PS and PE diets. Beeswax and bran showed different shaping effects on the core gut microbiome of larvae fed the PE and PS. These results suggest that supplementing the co-diet affected the physiological properties of the larvae and plastic biodegradation and shaped the core gut microbiome.


Asunto(s)
Microbioma Gastrointestinal , Mariposas Nocturnas , Animales , Suplementos Dietéticos , Larva , Plásticos , Polietileno , Poliestirenos
16.
Phys Chem Chem Phys ; 22(2): 818-825, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31840726

RESUMEN

Doping homogeneity is important for the properties of co-doped phosphors, as it can affect the energy transfer between sensitizer and activator ions. In a case study we apply different methods, that is scanning electron microscopy (SEM) combined with energy dispersive X-ray spectroscopy (EDX) mapping, SEM combined with cathodoluminescence (CL) and solid-state nuclear magnetic resonance (NMR), to study the doping homogeneity of the host system monazite LaPO4 doped with two different lanthanide ions on different length scales. A new criterion for doping heterogeneity in co-doped systems is developed, which is based on the NMR visibility function, which for this purpose is extended to doping with two or more paramagnetic dopants. A deviation from this function is indicative of doping heterogeneity on the length-scale of the blind-spheres of the paramagnetic dopants. A discussion of the advantages and disadvantages of the different methods is presented. The combined approach allows to study doping homogeneity from the nm to the µm scale.

17.
Appl Microbiol Biotechnol ; 104(24): 10389-10408, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33175245

RESUMEN

Sulfonamides are the oldest class of synthetic antibiotics still in use in clinical and veterinary settings. The intensive utilization of sulfonamides has been leading to the widespread contamination of the environment with these xenobiotic compounds. Consequently, in addition to pathogens and commensals, also bacteria inhabiting a wide diversity of environmental compartments have been in contact with sulfonamides for almost 90 years. This review aims at giving an overview of the effect of sulfonamides on bacterial cells, including the strategies used by bacteria to cope with these bacteriostatic agents. These include mechanisms of antibiotic resistance, co-metabolic transformation, and partial or total mineralization of sulfonamides. Possible implications of these mechanisms on the ecosystems and dissemination of antibiotic resistance are also discussed. KEY POINTS: • Sulfonamides are widespread xenobiotic pollutants; • Target alteration is the main sulfonamide resistance mechanism observed in bacteria; • Sulfonamides can be modified, degraded, or used as nutrients by some bacteria.


Asunto(s)
Ecosistema , Sulfonamidas , Antibacterianos/farmacología , Bacterias , Biodegradación Ambiental , Farmacorresistencia Microbiana
18.
Childs Nerv Syst ; 36(6): 1215-1222, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31222445

RESUMEN

INTRODUCTION: Tumors of the cerebellum are the most common brain tumors in children. Modern treatment and aggressive surgery have improved the overall survival. Consequently, growing numbers of survivors are at high risk for developing adverse and long-term neurological deficits including deficits of cognition, behavior, speech, and language. Post-operative cerebellar mutism syndrome (pCMS) is a well-known and frequently occurring complication of cerebellar tumor surgery in children. In the acute stage, children with pCMS may show deterioration of cerebellar motor function as well as pyramidal and cranial neuropathies. Most debilitating is the mutism or the severe reduction of speech and a range of neurobehavioral symptoms that may occur. In the long term, children that recover from pCMS continue to have more motor, behavioral, and cognitive problems than children who did not develop pCMS after cerebellar tumor surgery. The severity of these long-term sequelae seems to be related to the length of the mute phase. AIM OF THIS NARRATIVE REVIEW: The impact of pCMS on patients and families cannot be overstated. This contribution aims to discuss the present knowledge on the natural course, recovery, and rehabilitation of children with pCMS. We suggest future priorities in developing rehabilitation programs in order to improve the long-term quality of life and participation of children after cerebellar tumor surgery and after pCMS in particular.


Asunto(s)
Enfermedades Cerebelosas , Neoplasias Cerebelosas , Mutismo , Enfermedades Cerebelosas/etiología , Neoplasias Cerebelosas/cirugía , Cerebelo , Niño , Humanos , Mutismo/etiología , Complicaciones Posoperatorias/etiología , Calidad de Vida
19.
Molecules ; 25(6)2020 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-32197427

RESUMEN

The world is confronted with the depletion of natural resources due to their unsustainable use and the increasing size of populations. In this context, the efficient use of by-products, residues and wastes generated from agro-industrial and food processing opens the perspective for a wide range of benefits. In particular, legume residues are produced yearly in very large amounts and may represent an interesting source of plant proteins that contribute to satisfying the steadily increasing global protein demand. Innovative biorefinery extraction cascades may also enable the recovery of further bioactive molecules and fibers from these insufficiently tapped biomass streams. This review article gives a summary of the potential for the valorization of legume residual streams resulting from agro-industrial processing and more particularly for pea, green bean and chickpea by-products/wastes. Valuable information on the annual production volumes, geographical origin and state-of-the-art technologies for the extraction of proteins, fibers and other bioactive molecules from this source of biomass, is exhaustively listed and discussed. Finally, promising applications, already using the recovered fractions from pea, bean and chickpea residues for the formulation of feed, food, cosmetic and packaging products, are listed and discussed.


Asunto(s)
Biomasa , Cicer/química , Fitoquímicos , Pisum sativum/química , Administración de Residuos , Residuos , Fitoquímicos/química , Fitoquímicos/aislamiento & purificación
20.
Bull Environ Contam Toxicol ; 104(5): 701-706, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32236703

RESUMEN

The accumulation and transformation of 2,2',4,4'-tetrabrominated diphenyl ether (BDE47), one congener of the flame retardants polybrominated diphenyl ethers (PBDEs), in soil-feeding fauna are still unknown. Using radioactivity tracer, we incubated 14C-labelled BDE47 in soil for 21 days in the presence and absence of the geophagous earthworm Metaphire vulgaris. BDE47 accumulated in the earthworm predominantly via oral ingestion of soil, giving a biota-soil accumulation factor (BSAF) value of 1.3 for radioactivity at the end of incubation, and was mostly located in intestine, followed by clitellum (organs region) and skin of earthworms. Accumulation was accompanied by significant decrease of BDE47 concentration in soil porewater and BDE47 mineralization in soil. BDE47 was transformed in the earthworm gut into two metabolites with higher polarities than BDE47. The results provide for the first time insights into accumulation and transformation of lower-brominated congeners of PBDEs in geophagous earthworms, being helpful for environmental risk assessment of PBDEs.


Asunto(s)
Bioacumulación , Retardadores de Llama/análisis , Éteres Difenilos Halogenados/análisis , Oligoquetos/metabolismo , Contaminantes del Suelo/análisis , Suelo/química , Animales , Retardadores de Llama/metabolismo , Éteres Difenilos Halogenados/metabolismo , Contaminantes del Suelo/metabolismo
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