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1.
Mar Drugs ; 20(6)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35736160

RESUMO

Artina pectinata (Comb pen shell, CPS) is a high-protein source that contains a variety of essential amino acids. Subcritical water hydrolysis (SWH) was used to recover amino acids from the posterior adductor muscle (PAM), anterior adductor muscle (ADM), and mantle. The temperatures ranged from 120 °C to 200 °C, and the pressure and time of hydrolysis were 3 MPa and 30 min, respectively. Further characterization of the hydrolysates was performed to ascertain amino acid profiles and biofunctional properties. The hydrolysates contained more free amino acids than the untreated samples. Antioxidant activity of treated samples increased as SW temperatures increased. At 200 °C, those inhibiting ACE had a maximum antihypertensive activity of 200 °C in 1% PAM, ADM, and mantle with 85.85 ± 0.67, 84.55 ± 0.18, and 82.15 ± 0.85%, respectively, compared to 97.57 ± 0.67% in 1% standard captopril. Perhaps the most significant finding was the predominance of taurine in the three parts following SW treatment at 120 °C. The hydrolysates may be of considerable interest for use in food or energy drinks. SWH demonstrates efficacy in recovering amino acids, particularly taurine, from edible parts of A. pectinata.


Assuntos
Bivalves , Água , Aminoácidos , Animais , Hidrólise , Taurina , Água/química
2.
Mar Drugs ; 19(3)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33804423

RESUMO

The recovery of amino acids and other important bioactive compounds from the comb penshell (Atrina pectinata) using subcritical water hydrolysis was performed. A wide range of extraction temperatures from 140 to 290 °C was used to evaluate the release of proteins and amino acids. The amount of crude protein was the highest (36.14 ± 1.39 mg bovine serum albumin/g) at 200 °C, whereas a further increase in temperature showed the degradation of the crude protein content. The highest amount of amino acids (74.80 mg/g) was at 230 °C, indicating that the temperature range of 170-230 °C is suitable for the extraction of protein-rich compounds using subcritical water hydrolysis. Molecular weights of the peptides obtained from comb penshell viscera decreased with the increasing temperature. SDS-PAGE revealed that the molecular weight of peptides present in the hydrolysates above the 200 °C extraction temperature was ≤ 1000 Da. Radical scavenging activities were analyzed to evaluate the antioxidant activities of the hydrolysates. A. pectinata hydrolysates also showed a particularly good antihypertensive activity, proving that this raw material can be an effective source of amino acids and marine bioactive peptides.


Assuntos
Aminoácidos/isolamento & purificação , Antioxidantes/isolamento & purificação , Bivalves/química , Peptídeos/isolamento & purificação , Aminoácidos/química , Animais , Anti-Hipertensivos/química , Anti-Hipertensivos/isolamento & purificação , Anti-Hipertensivos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Eletroforese em Gel de Poliacrilamida , Humanos , Hidrólise , Peso Molecular , Peptídeos/química , Peptídeos/farmacologia , Temperatura , Vísceras , Água/química
3.
J Neurophysiol ; 121(5): 1761-1777, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30840520

RESUMO

Fear conditioning studies have led to the view that the amygdala contains neurons that signal threat and in turn elicit defensive behaviors through their brain stem and hypothalamic targets. In agreement with this model, a prior unit-recording study in rats performing a seminaturalistic foraging task revealed that many lateral amygdala (LA) neurons are predator responsive. In contrast, our previous study emphasized that most basolateral (BL) amygdala neurons are inhibited at proximity of the predator. However, the two studies used different methods to analyze unit activity, complicating comparisons between them. By applying the same method to the sample of BL neurons we recorded previously, the present study revealed that most principal cells are inhibited by the predator and only 4.5% are activated. Moreover, two-thirds of these cells were also activated by nonthreatening stimuli. In fact, fitting unit activity with a generalized linear model revealed that the only task variables associated with a prevalent positive modulation of BL activity were expectation of the predator's presence and whether the prior trial had been a failure or success. At odds with the threat-coding model of the amygdala, actual confrontation with the predator was usually associated with a widespread inhibition of principal BL neurons. NEW & NOTEWORTHY The basolateral amygdala (BL) is thought to contain neurons that signal threat, in turn eliciting defensive behaviors. In contrast, the present study reports that very few principal BL cells are responsive to threats and that most of them are also activated by nonthreatening stimuli. Yet, expectation of the threat's presence was associated with a prevalent positive modulation of BL activity; actual confrontation with the threat was associated with a widespread inhibition.


Assuntos
Tonsila do Cerebelo/fisiologia , Condicionamento Clássico , Medo , Neurônios/fisiologia , Potenciais de Ação , Tonsila do Cerebelo/citologia , Animais , Masculino , Inibição Neural , Ratos , Ratos Sprague-Dawley
4.
Reprod Fertil Dev ; 29(2): 357-367, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26293544

RESUMO

To study gene expression and to determine distinctive characteristics of embryos produced by different methods, normalisation of the gene(s) of interest against reference gene(s) has commonly been employed. Therefore, the present study aimed to assess which reference genes tend to express more stably in single porcine blastocysts produced in vivo (IVO) or by parthenogenetic activation (PA), in vitro fertilisation (IVF) and somatic cell nuclear transfer (SCNT) using different analysis programs, namely geNorm, Normfinder and Bestkeeper. Commonly used reference genes including 18S rRNA (18S), H2A histone family, member Z (H2A), hypoxanthine phosphoribosyltransferase1 (HPRT1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), ribosomal protein 4 (RPL4), peptidylprolyl isomerase A (PPIA), beta actin (ACTB), succinate dehydrogenase complex, subunit A (SDHA) and hydroxymethylbilane synthase (HMBS2) were analysed; most of them resulted in significantly (P<0.05) different cycle threshold (CT) values in porcine embryos except for SDHA and H2A. In evaluation of stable reference genes across in vivo and in vitro porcine blastocysts, three kinds of programs showed slightly different results; however, there were similar patterns about the rankings of more or less stability overall. In conclusion, SDHA and H2A were determined as the most appropriate reference genes for reliable normalisation in order to find the comparative gene expression in porcine blastocysts produced by different methods, whereas 18S was regarded as a less-stable reference gene. The present study has evaluated the stability of commonly used reference genes for accurate normalisation in porcine embryos to obtain reliable results.


Assuntos
Embrião de Mamíferos/metabolismo , Perfilação da Expressão Gênica/métodos , Genes Essenciais , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Suínos
5.
Artigo em Inglês | MEDLINE | ID: mdl-28920769

RESUMO

The aim of this study was to investigate Cr(VI) removal from chromium-plating rinse water using modacrylic anion-exchange fibers (KaracaronTM KC31). Batch experiments were performed with synthetic Cr(VI) solutions to characterize the KC31 fibers in Cr(VI) removal. Cr(VI) removal by the fibers was affected by solution pH; the Cr(VI) removal capacity was the highest at pH 2 and decreased gradually with a pH increase from 2 to 12. In regeneration and reuse experiments, the Cr(VI) removal capacity remained above 37.0 mg g-1 over five adsorption-desorption cycles, demonstrating that the fibers could be successfully regenerated with NaCl solution and reused. The maximum Cr(VI) removal capacity was determined to be 250.3 mg g-1 from the Langmuir model. In Fourier-transform infrared spectra, a Cr = O peak newly appeared at 897 cm-1 after Cr(VI) removal, whereas a Cr-O peak was detected at 772 cm-1 due to the association of Cr(VI) ions with ion-exchange sites. X-ray photoelectron spectroscopy analyses demonstrated that Cr(VI) was partially reduced to Cr(III) after the ion exchange on the surfaces of the fibers. Batch experiments with chromium-plating rinse water (Cr(VI) concentration = 1178.8 mg L-1) showed that the fibers had a Cr(VI) removal capacity of 28.1-186.4 mg g-1 under the given conditions (fiber dose = 1-10 g L-1). Column experiments (column length = 10 cm, inner diameter = 2.5 cm) were conducted to examine Cr(VI) removal from chromium-plating rinse water by the fibers under flow-through column conditions. The Cr(VI) removal capacities for the fibers at flow rates of 0.5 and 1.0 mL min-1 were 214.8 and 171.5 mg g-1, respectively. This study demonstrates that KC31 fibers are effective in the removal of Cr(VI) ions from chromium-plating rinse water.


Assuntos
Resinas Acrílicas/química , Resinas de Troca Aniônica/química , Cromo/análise , Cloreto de Polivinila/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Cromo/química , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/química
6.
J Neurosci ; 35(38): 12994-3005, 2015 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-26400931

RESUMO

We recorded basolateral amygdala (BL) neurons in a seminaturalistic foraging task. Rats had to leave their nest to retrieve food in an elongated arena inhabited by a mechanical predator. There were marked trial-to-trial variations in behavior. After poking their head into the foraging arena and waiting there for a while, rats either retreated to their nest or initiated foraging. Before initiating foraging, rats waited longer on trials that followed failed than successful trials indicating that prior experience influenced behavior. Upon foraging initiation, most principal cells (Type-1) reduced their firing rate, while in a minority (Type-2) it increased. When rats aborted foraging, Type-1 cells increased their firing rates, whereas in Type-2 cells it did not change. Surprisingly, the opposite activity profiles of Type-1 and Type-2 units were also seen in control tasks devoid of explicit threats or rewards. The common correlate of BL activity across these tasks was movement velocity, although an influence of position was also observed. Thus depending on whether rats initiated movement or not, the activity of BL neurons decreased or increased, regardless of whether threat or rewards were present. Therefore, BL activity not only encodes threats or rewards, but is closely related to behavioral output. We propose that higher order cortical areas determine task-related changes in BL activity as a function of reward/threat expectations and internal states. Because Type-1 and Type-2 cells likely form differential connections with the central amygdala (controlling freezing), this process would determine whether movement aimed at attaining food or exploration is suppressed or facilitated. Significance statement: For decades, amygdala research has been dominated by pavlovian and operant conditioning paradigms. This work has led to the view that amygdala neurons signal threats or rewards, in turn causing defensive or approach behaviors. However, the artificial circumstances of conditioning studies bear little resemblance to normal life. In natural conditions, subjects are simultaneously presented with potential threats and rewards, forcing them to engage in a form of risk assessment. We examined this process using a seminaturalistic foraging task. In constant conditions of threats and rewards, amygdala activity could be high or low, depending on the rats' decisions on a given trial. Therefore, amygdala activity does not only encode threats or rewards but is also closely related to behavioral output.


Assuntos
Tonsila do Cerebelo/fisiologia , Condicionamento Operante/fisiologia , Meio Ambiente , Medo/psicologia , Comportamento Alimentar/fisiologia , Potenciais de Ação/fisiologia , Tonsila do Cerebelo/citologia , Animais , Comportamento de Escolha/fisiologia , Comportamento Exploratório , Neurônios/classificação , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Recompensa , Robótica
7.
J Neurosci ; 34(39): 13170-82, 2014 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-25253862

RESUMO

Gap junctions (GJs) electrically couple GABAergic neurons of the forebrain. The spatial organization of neuron clusters coupled by GJs is an important determinant of network function, yet it is poorly described for nearly all mammalian brain regions. Here we used a novel dye-coupling technique to show that GABAergic neurons in the thalamic reticular nucleus (TRN) of mice and rats form two types of GJ-coupled clusters with distinctive patterns and axonal projections. Most clusters are elongated narrowly along functional modules within the plane of the TRN, with axons that selectively inhibit local groups of relay neurons. However, some coupled clusters have neurons arrayed across the thickness of the TRN and target their axons to both first- and higher-order relay nuclei. Dye coupling was reduced, but not abolished, among cells of connexin36 knock-out mice. Our results suggest that GJs form two distinct types of inhibitory networks that correlate activity either within or across functional modules of the thalamus.


Assuntos
Sinapses Elétricas/fisiologia , Neurônios GABAérgicos/fisiologia , Núcleos Intralaminares do Tálamo/citologia , Animais , Axônios/metabolismo , Axônios/fisiologia , Conexinas/genética , Conexinas/metabolismo , Sinapses Elétricas/metabolismo , Neurônios GABAérgicos/citologia , Neurônios GABAérgicos/metabolismo , Interneurônios/citologia , Interneurônios/metabolismo , Interneurônios/fisiologia , Núcleos Intralaminares do Tálamo/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Inibição Neural , Ratos , Ratos Sprague-Dawley , Proteína delta-2 de Junções Comunicantes
8.
J Biol Chem ; 289(47): 32512-25, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25294882

RESUMO

The spinal cord does not spontaneously regenerate, and treatment that ensures functional recovery after spinal cord injury (SCI) is still not available. Recently, fibroblasts have been directly converted into induced neural stem cells (iNSCs) by the forced expression defined transcription factors. Although directly converted iNSCs have been considered to be a cell source for clinical applications, their therapeutic potential has not yet been investigated. Here we show that iNSCs directly converted from mouse fibroblasts enhance the functional recovery of SCI animals. Engrafted iNSCs could differentiate into all neuronal lineages, including different subtypes of mature neurons. Furthermore, iNSC-derived neurons could form synapses with host neurons, thus enhancing the locomotor function recovery. A time course analysis of iNSC-treated SCI animals revealed that engrafted iNSCs effectively reduced the inflammatory response and apoptosis in the injured area. iNSC transplantation also promoted the active regeneration of the endogenous recipient environment in the absence of tumor formation. Therefore, our data suggest that directly converted iNSCs hold therapeutic potential for treatment of SCI and may thus represent a promising cell source for transplantation therapy in patients with SCI.


Assuntos
Células-Tronco Pluripotentes Induzidas/transplante , Células-Tronco Neurais/transplante , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/terapia , Animais , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Embrião de Mamíferos/citologia , Potencial Evocado Motor/genética , Potencial Evocado Motor/fisiologia , Feminino , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Imuno-Histoquímica , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos Endogâmicos C3H , Microscopia de Fluorescência , Regeneração Nervosa/genética , Regeneração Nervosa/fisiologia , Nestina/genética , Nestina/metabolismo , Células-Tronco Neurais/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/genética , Recuperação de Função Fisiológica/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Traumatismos da Medula Espinal/genética , Sinapses/metabolismo , Sinapses/fisiologia
9.
Ophthalmologica ; 229(3): 152-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23257663

RESUMO

BACKGROUND/AIMS: To evaluate the effectiveness of intravitreal ranibizumab injection (IVRI) for acute central serous chorioretinopathy (CSC). METHODS: Patients with symptomatic CSC of less than 3 months were prospectively recruited. Patients (n = 20/group) were randomly assigned to IVRI (0.5 mg/0.05 ml) or observation and followed for 6 months. logMAR best-corrected visual acuity (BCVA), fluorescein angiography, indocyanine angiography, and central foveal thickness (CFT) were assessed at baseline and at regular follow-ups. RESULTS: All patients had increased BCVA, decreased CFT, and resolution of the neurosensory detachment. Complete resolution of neurosensory retinal detachment required more time in the observation group (13.0 ± 3.1 vs. 4.2 ± 0.9 weeks; p < 0.001). Mean BCVA and mean CFT improved significantly in both groups, but the changes were not significantly different between groups at 6 months. CONCLUSIONS: IVRI for acute CSC might hasten resolution of neurosensory detachment compared to observation alone. At 6 months, BCVA and CFT did not differ between IVRI and observation groups. Further studies are required to determine the long-term benefits of IVRI.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Coriorretinopatia Serosa Central/tratamento farmacológico , Doença Aguda , Adulto , Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Coriorretinopatia Serosa Central/diagnóstico , Coriorretinopatia Serosa Central/fisiopatologia , Corantes , Feminino , Angiofluoresceinografia , Humanos , Verde de Indocianina , Injeções Intravítreas , Masculino , Estudos Prospectivos , Ranibizumab , Descolamento Retiniano/tratamento farmacológico , Descolamento Retiniano/fisiopatologia , Resultado do Tratamento , Acuidade Visual/fisiologia
10.
Lasers Med Sci ; 28(5): 1289-96, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23179311

RESUMO

High success rates in clinical trials on keratoconic corneas suggest the possibility of efficient treatment against myopic progression. This study quantitatively investigated the in vitro ultrastructural effects of a photooxidative collagen cross-linking treatment with photosensitizer riboflavin and UVA light in human corneo-scleral collagen fibrils. A total of 30.8 × 2 mm corneo-scleral strips from donor tissue were sagittally dissected using a scalpel. The five analytic parameters namely fibril density, fibril area, corneo-scleral thickness, fibril diameter, and fibril arrangement were investigated before and after riboflavin-UVA-catalyzed collagen cross-linking treatment. Collagen cross-linking effects were measured at the corneo-scleral stroma and were based on clinical corneal cross-linking procedures. The structural response levels were assessed by histology, digital mechanical caliper measurement, scanning electron microscopy, and atomic force microscopy. Riboflavin-UVA-catalyzed collagen cross-linking treatment led to an increase in the area, density, and diameters of both corneal (110, 112, and 103 %) and scleral (133, 133, and 127 %) stromal collagens. It also led to increases in corneal (107 %) and scleral (105 %) thickness. Collagen cross-linking treatment through riboflavin-sensitized photoreaction may cause structural property changes in the collagen fibril network of the cornea and sclera due to stromal edema and interfibrillar spacing narrowing. These changes were particularly prominent in the sclera. This technique can be used to treat progressive keratoconus in the cornea as well as progressive myopia in the sclera. Long-term collagen cross-linking treatment of keratoconic and myopic progression dramatically improves weakened corneo-scleral tissues.


Assuntos
Colágeno/efeitos dos fármacos , Colágeno/efeitos da radiação , Córnea/efeitos dos fármacos , Córnea/efeitos da radiação , Riboflavina/farmacologia , Esclera/efeitos dos fármacos , Esclera/efeitos da radiação , Terapia Ultravioleta , Adulto , Colágeno/química , Córnea/química , Reagentes de Ligações Cruzadas , Humanos , Técnicas In Vitro , Ceratocone/tratamento farmacológico , Ceratocone/radioterapia , Masculino , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Miopia/tratamento farmacológico , Miopia/radioterapia , Fármacos Fotossensibilizantes/farmacologia , Esclera/química
11.
Environ Sci Pollut Res Int ; 30(17): 49703-49719, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36780080

RESUMO

Acetaminophen (AAP) is an analgesic and non-steroidal anti-inflammatory drug and a micropollutant that has been detected in waterbodies worldwide. Here, we explore the characteristics of AAP adsorption onto spherical carbons (SCs) hydrothermally synthesized from pure sucrose as a carbon source. In one-factor-at-a-time experiments, the adsorption capacity of AAP remained relatively constant between pH 2 and 10 but became negligible at pH 12. The Raman, FTIR, and XPS spectra illustrate that hydrogen bonding, π-π interactions, and n-π* interactions could contribute to the AAP adsorption onto the SCs. CHEM3D modeling was used to explore hydrogen-bond formation, π-π interactions, n-π* interactions, and electrostatic repulsion between AAP and the SCs. In view of the pHpzc of the SCs (3.1) and the pKa of AAP (10.96), electrostatic repulsion could occur between negatively charged SCs and anionic AAP above pH 10. In consideration of the average pore diameter of the SCs (1.89 nm) and the AAP molecular size (8.94 Å × 7.95 Å × 4.93 Å), a pore-filling mechanism could contribute to the adsorption. A pseudo-second-order model was best fitted to the kinetic data (equilibrium time = 6 h), whereas the Liu isotherm was most suitable for the equilibrium data (maximum adsorption capacity = 92.0 mg/g). Adsorption of AAP to the SCs was exothermic at 10-40 °C. The SCs were regenerated and reused for AAP adsorption using a methanol. Multiple-factor-at-once (MFAO) experiments (input variables: pH, temperature, adsorbent dosage, and initial AAP concentration; output: AAP adsorption capacity) were used to develop response surface methodology (RSM, quartic regression) and artificial neural network (ANN, topology 4:11:9:1) models. Analyses using additional MFAO experimental data reveal that the predictive ability of the ANN model (R2 = 0.890) was better than that of the RSM model (R2 = 0.764). Based on the weight values of the ANN model, the relative importance of the input variables on the output was quantified in the order of initial AAP concentration (100%) > adsorbent dosage (92.3%) > temperature (77.6%) > pH (43.6%).


Assuntos
Acetaminofen , Poluentes Químicos da Água , Adsorção , Carbono , Temperatura , Modelos Teóricos , Cinética , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio , Termodinâmica
12.
Chemosphere ; 311(Pt 1): 137074, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36332741

RESUMO

Ibuprofen (IPF) is one of the most prescribed nonsteroidal anti-inflammatory drugs in recent times, but it is not readily removed in conventional wastewater treatments. Here, we investigate the adsorption characteristics of IPF onto calcined spherical hydrochar (CSH), which was synthesized through hydrothermal carbonization of sucrose followed by calcination. The adsorption experiments show that the equilibration time for IPF was 360 min, and a pseudo-second-order model was best fitted to the kinetic data. The isotherm data were best described by the Liu model with a theoretical maximum adsorption capacity of 95.6 mg/g. The thermodynamic data indicate the endothermic nature of the adsorption at 10-40 °C. The CSH was favorably regenerated and reused using methanol. In pH experiments, the IPF adsorption capacity declined gradually as pH rose from 2 to 8, dropped rapidly at pH 10, and became negligible at pH 12. The IPF adsorption to the CSH could occur through various adsorption mechanisms. Hydrogen-bond formation, π-π interactions, n-π* interactions, and electrostatic repulsion were explored and visualized with molecular modeling using CHEM3D. The Raman, FTIR, and XPS spectra suggest that π-π interactions could take place between the CSH and IPF. Considering the pKa value of IPF (4.91) and pHiep of the CSH (3.21), electrostatic repulsion between the negatively-charged CSH and anionic IPF could play a negative role in the adsorption. A pore-filling mechanism could contribute to the adsorption in view of the molecular size of IPF (9.43 Å × 7.75 Å × 6.23 Å) and the average pore diameter of the CSH (2.27 nm). In addition, hydrophobic interactions could be involved in the adsorption. Multi-factor adsorption experiments were executed with pH, temperature, CSH dosage, and initial IPF concentrations as input variables and IPF removal rate as an output variable, and an artificial neural network (ANN) model with a topology of 4:9:11:1 was developed to sufficiently describe the adsorption data (R > 0.99). Further analyses with additional experimental data confirm that the ANN model possessed good predictability for multi-factor adsorption.


Assuntos
Ibuprofeno , Poluentes Químicos da Água , Adsorção , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Redes Neurais de Computação , Cinética , Termodinâmica
13.
Food Sci Nutr ; 11(9): 5223-5235, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37701233

RESUMO

Chemical risk assessment is important for risk management, and estimates of chemical exposure must be as accurate as possible. Chemical concentrations in food below the limit of detection are known as nondetects and result in left-censored data. During statistical analysis, the method used for handling values below the limit of detection is important. Many risk assessors employ widely used substitution methods to treat left-censored data, as recommended by international organizations. The National Institute of Food and Drug Safety Evaluation of South Korea also recommends these methods, which are currently used for chemical exposure assessments. However, these methods have statistical limitations, and international organizations recommend more advanced alternative statistical approaches. In this study, we assessed the validity of currently used statistical methods for handling nondetects. To identify the most suitable statistical method for handling nondetection, we created virtual data and conducted simulation studies. Based on both simulation and case studies, the Maximum Likelihood Estimation (MLE) and Robust Regression on Order Statistics (ROS) methods were found to be the best options. The statistical values obtained from these methods were similar to those obtained from the commonly used 1/2 Limit of Detection (LOD) substitution method for nondetection treatment. In three case studies, we compared the various methods based on the root mean squared error. The data for all case studies were from the same source, to avoid heterogeneity. Across various sample sizes and nondetection rates, the mean and 95th percentile values for all treatment methods were similar. However, "lognormal maximum likelihood estimation" method was not suitable for estimating the mean. Risk assessors should consider statistical processing of monitoring data to reduce uncertainty. Currently used substitution methods are effective and easy to apply to large datasets with nondetection rates <80%. However, advanced statistical methods are required in some circumstances, and national guidelines are needed regarding their use in risk assessments.

14.
Cell Prolif ; 56(2): e13366, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36478274

RESUMO

Hemogenic endothelium (HE) plays a pivotal and inevitable role in haematopoiesis and can generate all blood and endothelial lineage cells in the aorta-gonad-mesonephros of mouse embryos. Whether definitive HE can prospectively isolate pure HE from human pluripotent stem cells that can spontaneously differentiate into heterogeneous cells remains unknown. Here, we identified and validated a CD34dim subpopulation with hemogenic potential. We also purified CD34 cells with a CXCR4- CD73- phenotype as a definitive HE population that generated haematopoietic stem cells and lymphocytes. The frequency of CXCR4- CD73- CD34dim was evidently increased by bone morphogenetic protein 4, and purified HE cells differentiated into haematopoietic cells with myeloid and T lymphoid lineages including Vδ2+ subset of γ/δ T cells. We developed a simple method to purify HE cells that were enriched in CD34dim cells. We uncovered an initial step in differentiating haematopoietic lineage cells that could be applied to basic and translational investigations into regenerative medicine.


Assuntos
Hemangioblastos , Células-Tronco Pluripotentes , Animais , Camundongos , Humanos , Hemangioblastos/metabolismo , Proteína Morfogenética Óssea 4/farmacologia , Proteína Morfogenética Óssea 4/metabolismo , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Antígenos CD34/metabolismo , Diferenciação Celular , Hematopoese , Linhagem da Célula
15.
Int J Biol Macromol ; 241: 124516, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37086762

RESUMO

Mercury (Hg) is widely used in many industrial processes and is released into the environment. Therefore, efficient removal of Hg from water is of vital importance worldwide. Here, we explored the adsorption characteristics of Hg(II) on polyethyleneimine-functionalized carboxymethylcellulose (PEI-CMC) beads and studied the toxicity of the beads toward Daphnia magna and Pseudokirchneriella subcapitata. The PEI-CMC beads had an average particle size of 2.04 ± 0.25 mm, a point of zero charge (pHpzc) of 5.8, and a swelling ratio of 2.45. Acute toxicity tests demonstrated that the PEI-CMC beads had no toxic effects on D. magna. The growth inhibition tests revealed that growth inhibition of P. subcapitata could be attributed to adsorption of trace elements in growth media on the PEI-CMC beads. The adsorption experiments exhibited that the Matthews and Weber model best described the kinetic data, whereas the Redlich-Peterson model was well fitted to the isotherm data. The theoretical maximum Hg(II) adsorption capacity of the PEI-CMC beads was 313.1 mg/g. The thermodynamic experiments showed endothermic nature of the Hg(II) adsorption on the PEI-CMC beads at 10-40 °C. The adsorption experiments exhibited that the Hg(II) adsorption capacity decreased gradually as pH increased from 2 to 12. The adsorption of Hg(II) on the PEI-CMC beads can occur through chelation and electrostatic attraction. The FTIR and XPS spectra before and after Hg(II) adsorption confirmed that chelation of neutral Hg(II) species (HgCl2, HgClOH, and Hg(OH)2) can occur with amino and oxygen-containing functional groups on the PEI-CMC beads. Considering species distribution of Hg(II) and the pHpzc of the PEI-CMC beads, electrostatic attraction between the positively-charged beads and anionic Hg(II) species (HgCl3- and HgCl42-) can take place in highly acidic solutions. The PEI-CMC beads were regenerated and reused for Hg(II) adsorption using 0.1 M HCl.


Assuntos
Polietilenoimina , Poluentes Químicos da Água , Polietilenoimina/química , Carboximetilcelulose Sódica/química , Adsorção , Cinética , Testes de Toxicidade , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
16.
Food Chem ; 388: 132949, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35436637

RESUMO

Green extraction methodologies using supercritical carbon dioxide (SC-CO2) and subcritical water were used to valorize Conger myriaster skin (CMS). The omega-3 fatty acid content in CMS oil extracted using SC-CO2 was 18.62 ± 0.08%, and vitamin A, D, E, and K2 contents were 467.38 ± 0.46 µg/100 g, 8.31 ± 0.02 mg/100 g, 143.42 ± 4.61 mg/100 g, and 1.27 ± 0.05 mg/100 g, respectively. De-oiled CMS was hydrolyzed using subcritical water at temperatures ranging from 160 to 280 °C. Total protein, total sugar, and Maillard reaction product contents reached maximum values of 409.31 ± 2.86 mg bovine serum albumin (BSA)/g at 190 °C, 8.31 ± 0.31 mg glucose/g at 280 °C, and 0.240 ± 0.003 (Abs420nm) at 220 °C, respectively. The highest antioxidant activity was observed at 280 °C. Free amino acids were abundant in the hydrolysates. Oil extraction from CMS using supercritical and subcritical fluids represents an effective and economical source of functional materials.


Assuntos
Dióxido de Carbono , Óleos de Plantas , Aminoácidos , Animais , Dióxido de Carbono/química , Enguias , Óleos de Plantas/química , Solventes/química , Temperatura , Água
17.
Am J Ophthalmol ; 239: 90-97, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35172169

RESUMO

PURPOSE: Development and validation of a decision tree model (DTM) for prediction of mental health status in Korean caregivers of children with glaucoma. DESIGN: Cross-sectional study. METHODS: Caregivers of children younger than 18 years with diagnosed primary childhood glaucoma (n = 42), secondary childhood glaucoma (n = 51), and glaucoma suspect (GS; n = 36) were prospectively enrolled at Seoul National University Children's Hospital, Seoul, Korea. The participants completed 2 questionnaires, the 9-item Patient Health Questionnaire (PHQ-9) and the 7-item Generalized Anxiety Disorder (GAD-7) Assessment. A DTM analysis for discrimination of those with moderate-to-severe depressive (PHQ-9 score ≥10) and anxiety (GAD-7 score ≥11) symptoms was performed with recursive partitioning algorithms based on the obtained clinical, demographic, and socioeconomic data. RESULTS: The mean PHQ-9 and GAD-7 scores did not significantly differ among the 3 groups (P = .823 for PHQ-9 score; P = .730 for GAD-7 score). The DTM's balanced accuracies were 0.875 (95% CI = 0.778-0.972) for the PHQ-9 score and 0.880 (95% CI = 0.800-0.960) for theGAD-7 score. The DTM of the PHQ-9 revealed that in caregivers of children with glaucoma, depressive symptoms should be strongly suspected when (1) the child has undergone more than 2 glaucoma surgeries; or (2) the visual acuity (VA, converted to logarithm of minimum angle of resolution [logMAR]) in the better eye is worse than 0.4 if the child has had only 1 or no surgery. CONCLUSIONS: Evaluation of the number of glaucoma surgeries and VA in the better eye can be a useful decision support tool in predicting mental illness in caregivers of children with glaucoma.


Assuntos
Cuidadores , Glaucoma , Algoritmos , Ansiedade , Cuidadores/psicologia , Criança , Estudos Transversais , Árvores de Decisões , Depressão/diagnóstico , Depressão/etiologia , Humanos , Inquéritos e Questionários
18.
J Ophthalmol ; 2022: 1703806, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35036002

RESUMO

PURPOSE: To analyze ocular manifestations, visual field (VF) pattern, and VF test performance in traumatic brain injury (TBI) and stroke patients. METHODS: This retrospective, cross-sectional study included 118 patients (236 eyes) with TBI and stroke who had undergone VF testing by standard automated perimetry with the central 24-2 threshold test. Clinical features including best-corrected visual acuity (BCVA), intraocular pressure (IOP), ocular manifestations, and VF test results including VF defect pattern, reliability, and global indices were analyzed and compared between the TBI and stroke patients. RESULTS: In TBI patients, ocular manifestations included strabismus (11.1%), cataract (4.2%), and glaucoma suspect (2.8%), whereas in stroke patients, cataract (15.2%), strabismus (8.5%), diabetic retinopathy (4.9%), extraocular movement (EOM) limitation (3.0%), glaucoma suspect (3.0%), nystagmus (2.4%), drusen (1.2%), and vitreous hemorrhage (1.2%) were found. The VF test results showed that 47 eyes (85.5%) in TBI and 86 (65.2%) in stroke had VF defect; in TBI, the scattered pattern was the most common (56.4%), followed by homonymous hemianopsia (14.5%), homonymous quadrantanopia (10.9%), and total defect (3.6%), whereas in stroke, homonymous hemianopsia was the most common (31.8%), followed by scattered pattern (16.7%), homonymous quadrantanopia (12.1%), and total defect (4.5%). Only 15 eyes (27.3%) in TBI and 32 (24.2%) in stroke showed reliable VF indices. The mean deviation (MD) was -10.5 ± 7.1 dB in TBI and -9.5 ± 6.8 dB in stroke, and the pattern standard deviation (PSD) was 4.9 ± 3.3 dB in TBI and 6.1 ± 3.9 dB in stroke, without statistically significant differences between the two groups. CONCLUSION: Various ocular manifestations were found, and a considerable proportion of patients were experiencing VF defects and showed unreliable VF test performance. Our findings suggest that accurate evaluation and rehabilitation of visual function should be a matter of greater concern and emphasis in the management of TBI and stroke patients, besides systemic diseases.

19.
Nat Commun ; 13(1): 1386, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35296648

RESUMO

The prefrontal cortex is involved in goal-directed behavior. Here, we investigate circuits of the PFC regulating motivation, reinforcement, and its relationship to dopamine neuron activity. Stimulation of medial PFC (mPFC) neurons in mice activated many downstream regions, as shown by fMRI. Axonal terminal stimulation of mPFC neurons in downstream regions, including the anteromedial thalamic nucleus (AM), reinforced behavior and activated midbrain dopaminergic neurons. The stimulation of AM neurons projecting to the mPFC also reinforced behavior and activated dopamine neurons, and mPFC and AM showed a positive-feedback loop organization. We also found using fMRI in human participants watching reinforcing video clips that there is reciprocal excitatory functional connectivity, as well as co-activation of the two regions. Our results suggest that this cortico-thalamic loop regulates motivation, reinforcement, and dopaminergic neuron activity.


Assuntos
Neurônios Dopaminérgicos , Objetivos , Animais , Axônios , Neurônios Dopaminérgicos/fisiologia , Humanos , Camundongos , Vias Neurais/fisiologia , Córtex Pré-Frontal/fisiologia , Tálamo
20.
J Nanosci Nanotechnol ; 11(5): 4557-61, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21780496

RESUMO

Recently, iridium complexes with phenylpyridine based ligands and phosphines, Ir(C(see text for symbol)N)2 (PPh3)(CN), [(C(see text for symbol)N) = dfppy, dfMeppy] are reported as blue phosphorescent OLED materials. These iridium complexes have novel blue color and emit light at 441 nm to 439 nm. However, these complexes have low external quantum efficiency because they exhibit less MLCT than iridium complexes with phenylpyridine, and some other ancillary ligands. To improve quantum efficiency of iridium complexes with phenylpyridine based ligands and phosphines, a time dependent density functional theory (TDDFT) study of these phosphors was performed. Using these results, this paper discusses how the ancillary ligand influences the emission peak, as well as the metal to ligand charge transfer (MLCT) transition efficiency.

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