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1.
Clin Park Relat Disord ; 10: 100238, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38318489

RESUMO

Functional tremor (FT) is the most common phenotype of functional movement disorders (FMD). Its diagnosis can often be challenging. While positive signs such as tremor variability, distractibility, and entrainment support a diagnosis of FT, these diagnostic clues may not always be present and can be challenging to assess. In this case series, we identify another examination technique which could be of value when assessing FT. In our Movement Disorders clinic, charts were retrospectively reviewed for relevant clinical information. Video examinations were conducted. Obtained videos were either synchronous, via the use of screen recording software during telehealth visits or asynchronous, from self-recorded home videos. In both settings, patients were instructed to self-record their tremor using their phone cameras. Three patients with FT or comorbid FT were identified as demonstrating a unique examination sign. Videos showed an improvement or suppression of the tremor when the phone was held by the affected hand. When compared to a patient with tremor-dominant Parkinson's disease serving as a control, this "selfie sign" was not observed. These observations are preliminary and larger studies are needed to confirm the usefulness of the selfie sign in diagnosing FT. Patient-recorded videos of their tremor can be a convenient and practical way of evaluating suspected FT, especially when paroxysmal or variable symptoms limit the usefulness of classic signs often assessed in the clinic.

2.
Food Res Int ; 173(Pt 1): 113218, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803536

RESUMO

High hydrostatic pressure (HHP) is extensively utilized in the field of food processing due to its remarkable ability to preserve the freshness of food. The potential antigenicity of ß-lactoglobulin (ß-LG) in whey protein isolate (WPI, 3%) treated by HHP was detected by enzyme linked immunosorbent assay (ELISA) using monoclonal antibodies. Furthermore, the impact of pressure-induced structural alterations on the emulsification properties and antioxidant activity of WPI was investigated. The findings revealed that pressures exceeding 300 MPa resulted in molecular aggregation, the formation of inter-molecular disulfide bonds, and an increase in surface hydrophobicity (H0). The percentage of ß-sheet decreased along with the pressure. The results showed the increment of α-helix and ß-turn with pressure. ELISA demonstrated a significant reduction in the antigenicity of ß-LG following HHP treatment (100-600 MPa), with a slight recovery observed at 300 MPa. These spatial structural modifications led to the unfolding of the ß-LG molecule, thereby enhancing its digestibility. Moreover, HHP treatment substantially improved the antioxidant properties, with the exposure to hydrophobic amino acids contributing to increased antioxidant properties and emulsion stability.


Assuntos
Antioxidantes , Lactoglobulinas , Proteínas do Soro do Leite , Antioxidantes/química , Pressão Hidrostática , Lactoglobulinas/química , Interações Hidrofóbicas e Hidrofílicas
3.
Fish Physiol Biochem ; 49(5): 939-949, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37632644

RESUMO

The blunt snout bream (Megalobrama amblycephala) is a typical hypoxia-sensitive fish, and hypoxia stress leads to reduced vitality and yield during aquaculture. To explore the specific adaptation mechanism under hypoxia, the blunt snout bream was treated with hypoxia (DO = 2.0 ± 0.1 mg/L) for 24 h, followed by 3 h of recovery. Our results depicted that the gill filament structure of blunt snout bream changed after hypoxia. During hypoxia for 24 h, the gill filament structure was altered, including a more than 80% expansion of the lamellar respiratory surface area and a proportionate apoptosis decrease in interlamellar cell mass (ILCM) volume. Thus, the water-blood diffusion distance was shortened to less than 46%. During hypoxia for 24 h, the activity of ROS in gill tissue increased significantly (p < 0.05), while the mitochondrial membrane potential decreased significantly (p < 0.05). During hypoxia, mRNA expression level of anti-apoptotic gene Bcl-2 in the gills of blunt snout bream decreased significantly (p < 0.05), while the expression of pro-apoptotic gene Bax mRNA increased significantly (p < 0.05). Thus, the ratio of Bax/Bcl-2 mRNA increased in the gills of blunt snout bream to promote the activity of Caspase-3. Together, our results indicated hypoxia-induced apoptosis in the gills of blunt snout bream through the mitochondrial pathway. In addition, a decreased expression of Phd1 and an increased expression of Hif-1α in gills under hypoxia stress indicates that blunt snout bream may cope with hypoxia-induced apoptosis by enhancing the HIF pathway. These results provide new insights into fish's adaptation strategies and mechanisms of hypoxia.


Assuntos
Cyprinidae , Cipriniformes , Animais , Brânquias/metabolismo , Cyprinidae/genética , Cyprinidae/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Cipriniformes/genética , Hipóxia/metabolismo , RNA Mensageiro/metabolismo , Expressão Gênica , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo
4.
Dev Cell ; 58(18): 1688-1700.e6, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37490911

RESUMO

The effectiveness of multiomics analyses in defining cell differentiation pathways during development is ambiguous. During liver development, hepatoblasts follow a default or directed pathway to differentiate into hepatocytes or cholangiocytes, respectively, and this provides a practical model to address this issue. Our study discovered that promoter-associated histone modifications and chromatin accessibility dynamics, rather than enhancer-associated histone modifications, effectively delineated the "default vs. directed" process of hepatoblast differentiation. Histone H3K27me3 on bivalent promoters is associated with this asymmetric differentiation strategy in mice and humans. We demonstrated that Ezh2 and Jmjd3 exert opposing regulatory roles in hepatoblast-cholangiocyte differentiation. Additionally, active enhancers, regulated by P300, correlate with the development of both hepatocytes and cholangiocytes. This research proposes a model highlighting the division of labor between promoters and enhancers, with promoter-associated chromatin modifications governing the "default vs. directed" differentiation mode of hepatoblasts, whereas enhancer-associated modifications primarily dictate the progressive development processes of hepatobiliary lineages.


Assuntos
Epigenômica , Hepatócitos , Camundongos , Humanos , Animais , Diferenciação Celular , Hepatócitos/metabolismo , Histonas/genética , Histonas/metabolismo , Cromatina/genética , Cromatina/metabolismo
5.
Int J Biol Macromol ; 244: 125479, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37336374

RESUMO

Reduced-fat food has become a popular choice among contemporary consumers. This study aims to develop a starch-based fat substitute and incorporate it into reduced-fat milk gel acidified with glucono-δ-lactone (GDL) to achieve similar rheological properties as a full-fat gel. The gel properties of the fat substitute were assessed. The study examined the rheological properties, syneresis, textural properties and microstructure of acidified milk gels while also monitoring acidification process. Starch hydrolysates with low dextrose equivalent (DE) (<5.1 %) can serve as an effective fat substitute due to their excellent gelling properties The rheological and textural properties of the reduced-fat acidified milk gel with DE at 3.1 % of starch hydrolysate and 30 % fat substitution are similar to those of the full-fat milk gel. The syneresis and confocal laser scanning microscopy (CLSM) results indicated that the microstructure of the reduced-fat acidified milk gel was similar to the full-fat version. Moreover, the sensory properties of the reduced-fat acidified milk gel were acceptable when the DE was 3.1 %, and 30 % fat was replaced. In our study, we utilized hydrolyzed starch to produce reduced-fat acidified milk gels, which could potentially be used in the development of reduced-fat yogurt formulations.


Assuntos
Substitutos da Gordura , Leite , Animais , Leite/química , Substitutos da Gordura/análise , Zea mays , Concentração de Íons de Hidrogênio , Géis/química , Reologia , Amido/análise
6.
J Clin Neurosci ; 114: 81-88, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37329664

RESUMO

BACKGROUND: Functional Neurologic Disorders (FND) are a common but heterogeneous group of disabling conditions. The Emergency Department (ED) is an important venue for care and referral as it is often the first point of contact when patients with FND are faced with a crisis or exacerbation of symptoms. METHODS: ED providers (n = 273) practicing in the Cleveland Clinic Foundation Northeast Ohio network were invited to participate through secure web application electronic surveys. Data were collected on practice profiles, knowledge, attitudes, management of FND, and awareness of available resources for FND. RESULTS: Sixty providers completed the survey (22% response rate; n = 50 ED physicians, 10 advanced care providers) with 95.0% (n = 57) reporting a lack of understanding about FND. The terms Psychogenic Nonepileptic Seizures and stress induced/stress related disease were used by 60.0% (n = 36) and 58.3% (n = 35) respectively. Ninety percent (n = 53) rated their experience with managing FND patients as at least more difficult. Eighty- five percent (n = 51) agreed with "rule out others" and 60% (n = 36) agreed with "caused by psych stress". Eighty six percent (n = 50) believe that there is a difference between FND from malingering. Only one respondent was familiar with any FND resources and 79% (n = 47) reported the need for FND specific educational materials. CONCLUSION: This survey revealed major gaps in knowledge, inaccurate perceptions, and management that differs from the current standard of care among ED providers caring for patients with FND. Educational opportunities are needed to guide diagnosis and evidence-based treatment to optimize management of patients with FND.


Assuntos
Transtorno Conversivo , Doenças do Sistema Nervoso , Humanos , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/terapia , Transtornos Psicofisiológicos , Serviço Hospitalar de Emergência
7.
Food Chem ; 405(Pt A): 134796, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36335724

RESUMO

An allergen epitope is a part of molecules that can specifically bind to immunoglobulin E (IgE), causing an allergic reactions. To predict protein epitopes and their binding ability to IgE, quantitative structure-activity relationship (QSAR) models were established using four algorithms combined with the selected chemical descriptors. The model predicted the binding capabilities of the epitopes to IgE with the R2 and root mean squared error (RMSE) as 0.7494 and 0.2375, respectively. The model's performance was validated using an enzyme-linked immunosorbent assay (ELISA). The results showed that the established QSAR model could efficiently and accurately predict the allergic reaction of food protein epitopes. The prediction results of the model and the experimental results were consistent, with a Pearson correlation coefficient of 0.8956. The results from both the QSAR model and in vitro experiments indicated that amino acid sequence 116-130 was a novel IgE-binding epitope of ß-LG.


Assuntos
Hipersensibilidade Alimentar , Humanos , Epitopos/química , Imunoglobulina E/metabolismo , Alérgenos/química , Aprendizado de Máquina
8.
Insights Imaging ; 13(1): 190, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36512153

RESUMO

BACKGROUND: Anterolateral thigh perforator (ALTP) flap is considered a versatile flap for soft tissue reconstruction. Computed tomography angiography (CTA) is used for mapping perforator in abdominal-based reconstruction; however, it is less commonly used in ALTP due to its poor imaging efficacy. In this study, we introduced a novel CTA technique for preoperative localization and design of ALTP flap and evaluated its value in directing surgical reconstruction. RESULTS: Thirty-five patients with soft tissue defects were consecutively enrolled. Modified CTA procedures, such as sharp convolution kernel, ADMIRE iterative reconstruction, 80 kV tube voltage, high flow contrast agent and cinematic rendering image reconstruction, were used to map ALTPs. A total of 287 perforators (including 884 sub-branches) were determined, with a mean of 5 perforators per thigh (range 2-11). The ALTPs were mainly concentrated in the "hot zone" (42%, 121/287) or the distal zone (41%, 118/287). Most perforators originated from the descending branch of the lateral circumflex femoral artery (76%, 219/287). Three perforator types, namely musculocutaneous (62%, 177/287), septocutaneous (33%, 96/287), and mixed pattern (5%, 14/287), were identified. The median pedicle length measured by two methods was 4.1 cm (range 0.7-20.3 cm) and 17.0 cm (range 4.7-33.9 cm), respectively, and the median diameter of the skin flap nourished by one perforator was 3.4 cm (IQR 2.1-5.7 cm). Twenty-eight ALTP flaps were obtained with the guidance of CTA, and 26 flaps survived after follow-up. CONCLUSIONS: The proposed CTA mapping technique is a useful tool for preoperative localization and design of ALTP flap.

10.
Clin Park Relat Disord ; 7: 100153, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909701

RESUMO

Dopamine agonist withdrawal syndrome (DAWS) has been introduced to describe the constellation of symptoms resulting from reduction or suspension of dopamine agonist medications. In patients with Parkinson's disease (PD) the impact of DAWS can be significant in terms of distress and disability. Unfortunately, no standard treatment exists other than reintroduce the dopamine agonist even in the presence of adverse effects. Therefore, identification of vulnerable patients would be beneficial. Previous studies have linked DAWS with impulse control disorder behavior (ICD), higher dopamine agonist doses, and milder motor impairment in PD patients. We conducted a retrospective chart review of PD patients treated with dopamine agonist. A total of 313 charts from January 2011 to December 2013 were reviewed, showing 126 patients who were discontinued from dopamine agonist. Twenty-one patients (16.8 %) fulfilled the diagnostic criteria for DAWS. Factors associated with the occurrence of DAWS were: (1) dose of dopamine agonist ≥150 mg expressed in levodopa equivalents daily dose (LEDD) (p = 0.018), (2) impulse control disorder as an adverse effect to dopamine agonist (p = 0.002), and (3) prior deep brain stimulation (DBS) (p = 0.049). The probability of developing DAWS in the presence of all 3 identified factors was 92 %; presence of 2 factors raised the probability up to 70 %; the presence of one factor increased the probability up to 30 %. In the absence of these 3 factors the probability of developing DAWS was 3 %. Prospective studies are warranted to confirm these findings.

11.
Diabetes ; 71(12): 2496-2512, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35880782

RESUMO

Caveolin-1 (cav1) is an important structural and signaling component of plasma membrane invaginations called caveolae and is abundant in adipocytes. As previously reported, adipocyte-specific ablation of the cav1 gene (ad-cav1 knockout [KO] mouse) does not result in elimination of the protein, as cav1 protein traffics to adipocytes from neighboring endothelial cells. However, this mouse is a functional KO because adipocyte caveolar structures are depleted. Compared with controls, ad-cav1KO mice on a high-fat diet (HFD) display improved whole-body glucose clearance despite complete loss of glucose-stimulated insulin secretion, blunted insulin-stimulated AKT activation in metabolic tissues, and partial lipodystrophy. The cause is increased insulin-independent glucose uptake by white adipose tissue (AT) and reduced hepatic gluconeogenesis. Furthermore, HFD-fed ad-cav1KO mice display significant AT inflammation, fibrosis, mitochondrial dysfunction, and dysregulated lipid metabolism. The glucose clearance phenotype of the ad-cav1KO mice is at least partially mediated by AT small extracellular vesicles (AT-sEVs). Injection of control mice with AT-sEVs from ad-cav1KO mice phenocopies ad-cav1KO characteristics. Interestingly, AT-sEVs from ad-cav1KO mice propagate the phenotype of the AT to the liver. These data indicate that ad-cav1 is essential for healthy adaptation of the AT to overnutrition and prevents aberrant propagation of negative phenotypes to other organs by EVs.


Assuntos
Caveolina 1 , Vesículas Extracelulares , Insulina , Animais , Camundongos , Adipócitos/metabolismo , Caveolina 1/genética , Caveolina 1/metabolismo , Dieta Hiperlipídica , Células Endoteliais/metabolismo , Vesículas Extracelulares/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Insulina Regular Humana , Camundongos Knockout
12.
Dalton Trans ; 51(7): 2962-2974, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35108721

RESUMO

The effective monitoring of water pollution and further purification are pressing yet challenging issues for guaranteeing the health of human beings and the stabilization of ecological systems. For this purpose, the development of efficient sensing and adsorption materials as a result of supramolecular interactions, including coordination and H-bonding etc., have been attracting increasing attention. With the aid of a coordination-driven self-assembly strategy, a new nonporous 2D CuII coordination network, [Cu2L(H2O)2]n (donated as CuCP), based on H4L, where H4L = 4-(4-(3,5-di-carboxy-pyridin-4-yl)phenyl)pyridine-2,6-dicarboxylic acid, was afforded hydrothermally. Structural analysis indicated that CuCP featured a wrinkled network similar to the ancient Chinese folding screens and constructed by the fully deprotonated ligand L4- with the coordination mode of bis(µ2-η1:η1:η2) and penta-coordinated Cu2+, which could be further upgraded to a supramolecular 3D framework as a result of the synergism of multiple C-H⋯O hydrogen bonds. The hydrostability of CuCP could be maintained within a wide pH range from 2 to 12 as verified by PXRD determination, endowing it with potential environmental applications. Thanks to the combination of the soft Lewis acidity of Cu2+ and its large conjugated structure, CuCP could be used as a turn-on fluorescence sensor for S2- and exhibited a different fluorescence response when Na2S, (NH4)2S or H2S were incorporated, even in actual water samples. The sensing mechanisms were disclosed in detail by the combination of experiments and density functional theory (DFT) calculations. Furthermore, CuCP was shown to be a selective and recoverable adsorbent with a maximum adsorption capacity of 379 mg g-1 in 60 minutes for methylene blue (MB). The adsorption mechanism could be a combination of π⋯π stacking, n⋯π interaction, aggregation effects and Soft and Hard Acid-Base theory (HSAB). The results presented herein open up new perspectives for CuII species in environmental applications.


Assuntos
Azul de Metileno
13.
Parkinsonism Relat Disord ; 92: 88-93, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34736157

RESUMO

INTRODUCTION: Non-motor DBS outcomes have received little attention in ET relative to PD. This study examines neuropsychological outcomes in ET following thalamic VIM DBS. METHODS: Fifty patients completed neuropsychological evaluations preoperatively and approximately seven months postoperatively. Cognition and mood changes were analyzed at the group level and individual level. Additional associations with treatment, disease, and demographic characteristics were assessed. RESULTS: Significant cognitive decline was not observed at the group level. At the individual level, 46% of patients demonstrated at least subtle overall cognitive decline (≥1SD on at least one test within at least two domains). Mild decline (≥1SD) was seen in 10%-29.17% of patients on individual tests across all cognitive domains, with highest rates in verbal memory. Substantial cognitive decline (≥2SD) occurred in less than 9% of the sample across all tests. Factors related to cognitive decline included higher DBS parameter settings, older age of ET onset, intracranial complications, and inability to reduce ET medications postoperatively. Depression and anxiety did not change when accounting for questionnaire items that could be falsely elevated by tremor. CONCLUSION: Substantial cognitive decline after VIM DBS is rare in patients with ET. However, subtle decrements can occur across cognitive domains and particularly in verbal memory. DBS parameter settings may relate to cognitive decline. Further research is needed to better understand possible associations with electrode lateralization and other variables that could also relate to disease progression and test-retest effects. Symptoms of depression and anxiety remain stable.


Assuntos
Disfunção Cognitiva/psicologia , Estimulação Encefálica Profunda/efeitos adversos , Tremor Essencial/psicologia , Tremor Essencial/cirurgia , Complicações Cognitivas Pós-Operatórias/psicologia , Afeto , Idoso , Cognição , Disfunção Cognitiva/epidemiologia , Estimulação Encefálica Profunda/métodos , Feminino , Humanos , Masculino , Memória , Testes Neuropsicológicos , Complicações Cognitivas Pós-Operatórias/epidemiologia , Período Pós-Operatório , Estudos Retrospectivos , Tálamo , Resultado do Tratamento , Comportamento Verbal
14.
Clin Park Relat Disord ; 4: 100091, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34316669

RESUMO

Dopamine agonists are one of the main stay of treatment option for Parkinson disease (PD). Side effects that develop from their use are generally categorized into behavioral and non-behavioral. Behavioral side effects include: impulse control behavior disorder (ICD), psychosis and cognitive impairment. Non-behavioral side effects include: nausea/vomiting, "sleep attacks", leg swelling, weight gain and orthostasis. The aim of this study is to evaluate the clinicians' response to PD patients who developed behavioral side effects from dopamine agonists, in comparison to those patients who developed only non-behavioral side effects. We performed a retrospective chart review of all patients diagnosed with PD over a two year period. Among 313 patients who were on a dopamine agonist, 156 reported side effects. Sixty-five patients reported behavioral (with or without non-behavioral) side effects, while 91 experienced only non-behavioral side effects. Forty-nine out of the 65 patients (75.3%) who experienced behavioral side effects had their dopamine agonist dose decreased compared to 53 out of 91patients (58.2%) who experienced only non-behavioral side effects (Chi square = 4.92, p < 0.05). Patients with behavioral side effects were 3 times more likely have their dose decreased (OR = 3.3; 95%CI = 1.442-7.551; P = 0.005). However, neither taper speed nor the occurrence of dopamine agonist withdrawal syndrome (DAWS) differed between the two groups. Amongst PD patients treated with dopamine agonists, the presence of behavioral side effects independently increased the chance of dopamine agonist dose reduction. Prospective studies are needed to confirm these findings.

15.
Cell Res ; 31(8): 886-903, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33692492

RESUMO

The pancreatic islet contains multiple hormone+ endocrine lineages (α, ß, δ, PP and ε cells), but the developmental processes that underlie endocrinogenesis are poorly understood. Here, we generated novel mouse lines and combined them with various genetic tools to enrich all types of hormone+ cells for well-based deep single-cell RNA sequencing (scRNA-seq), and gene coexpression networks were extracted from the generated data for the optimization of high-throughput droplet-based scRNA-seq analyses. These analyses defined an entire endocrinogenesis pathway in which different states of endocrine progenitor (EP) cells sequentially differentiate into specific endocrine lineages in mice. Subpopulations of the EP cells at the final stage (EP4early and EP4late) show different potentials for distinct endocrine lineages. ε cells and an intermediate cell population were identified as distinct progenitors that independently generate both α and PP cells. Single-cell analyses were also performed to delineate the human pancreatic endocrinogenesis process. Although the developmental trajectory of pancreatic lineages is generally conserved between humans and mice, clear interspecies differences, including differences in the proportions of cell types and the regulatory networks associated with the differentiation of specific lineages, have been detected. Our findings support a model in which sequential transient progenitor cell states determine the differentiation of multiple cell lineages and provide a blueprint for directing the generation of pancreatic islets in vitro.


Assuntos
Ilhotas Pancreáticas , Pâncreas , Animais , Diferenciação Celular , Linhagem da Célula , Humanos , Camundongos , Células-Tronco
16.
Food Chem ; 350: 129139, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33588281

RESUMO

ß-Lactoglobulin (ß-LG) is one of the major food allergens. Enzymatic hydrolysis is a promising strategy to reduce the antigenicity of ß-LG in industrial production. The relationship between the cleavage sites of ß-LG by protease and its antigenic active sites were explored in this study. Molecular docking and molecular dynamics (MD) were used to analyze the active sites and interaction force of ß-LG and IgG antibody. Whey protein was hydrolyzed by four specific enzymes and the antigenicity of the hydrolysates were determined by ELISA. The results of MD showed that the amino acid residue Gln155 (-4.48 kcal mol-1) played the most important roles in the process of binding. Hydrolysates produced by AY-10, which was the only one with specificity towards cleavage sites next to a Gln, had the lowest antigenicity at the same hydrolysis degree. Antigenicity decrease was related to the energy contribution of the cleavage site in the active sites.


Assuntos
Lactoglobulinas/imunologia , Lactoglobulinas/metabolismo , Simulação de Dinâmica Molecular , Peptídeo Hidrolases/metabolismo , Animais , Domínio Catalítico , Hidrólise , Imunoglobulina G/imunologia , Lactoglobulinas/química , Simulação de Acoplamento Molecular , Proteínas do Soro do Leite/metabolismo
17.
Dalton Trans ; 50(5): 1874-1886, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33475098

RESUMO

It is challenging to develop highly stable lanthanide luminescent sensors for detecting heavy metal ions and nitroaromatics in view of the human health and environmental security. To this end, two water stable Ln-MOFs with the chemical constitution of {[Ln(HL)]·3DMF·3H2O}n (Ln = Eu, LZG-Eu and Ln = Tb, LZG-Tb) have been developed solvothermally using a multidentate ligand (H4L) with the central phenyl backbone bisubstituted by 2,6-pyridine-dicarboxylic acid at the para-position, H4L = 1,4-bis(2',2'',6',6''-tetracarboxy-1,4':4,4''-pyridyl)benzene. Single crystal analysis demonstrates that two novel Ln-MOFs feature 4,4,4-connected nets with an unprecedented topology symbol of {42·6·83}2{42·62·82}{42·84} and contain two kinds of one-dimensional channels. Powder X-ray diffraction as well as the luminescence determination results indicate that they retain their crystallinity and structural integrity in harsh acidic and basic conditions with pH in the range of 4-11. Moreover, they are highly luminescent, which makes them excellent chemical sensors for detecting Cu2+ and 4-NP (4-nitrophenol) with high selectivity and sensitivity in aqueous media such as deionized water, tap water, and river water based on distinct quenching effects. To the best of our knowledge, their detection limits are lower than those documented so far. In addition, the quenching efficiency of 4-NP was retained in the presence of interfering ions even after the compounds were used for five cycles, which makes them attractive, reliable, visual, and recyclable luminescent Ln-MOF sensor materials for 4-NP. The recognition mechanism for Cu2+ could be attributed to the dissociation of the main framework induced by Cu2+ and the subsequent formation of a Cu2+ coordination species and that for 4-NP is considered to be multi-quenching mechanisms dominated by competition absorption.


Assuntos
Cobre/análise , Elementos da Série dos Lantanídeos/química , Substâncias Luminescentes/química , Nitrofenóis/análise , Água/química , Ligantes , Modelos Moleculares , Conformação Molecular
19.
Cell Res ; 31(3): 326-344, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33106598

RESUMO

Defining the precise regionalization of specified definitive endoderm progenitors is critical for understanding the mechanisms underlying the generation and regeneration of respiratory and digestive organs, yet the patterning of endoderm progenitors remains unresolved, particularly in humans. We performed single-cell RNA sequencing on endoderm cells during the early somitogenesis stages in mice and humans. We developed molecular criteria to define four major endoderm regions (foregut, lip of anterior intestinal portal, midgut, and hindgut) and their developmental pathways. We identified the cell subpopulations in each region and their spatial distributions and characterized key molecular features along the body axes. Dorsal and ventral pancreatic progenitors appear to originate from the midgut population and follow distinct pathways to develop into an identical cell type. Finally, we described the generally conserved endoderm patterning in humans and clear differences in dorsal cell distribution between species. Our study comprehensively defines single-cell endoderm patterning and provides novel insights into the spatiotemporal process that drives establishment of early endoderm domains.


Assuntos
Padronização Corporal/genética , Embrião de Mamíferos/citologia , Endoderma/citologia , Intestinos/citologia , Lábio/citologia , Animais , Células Cultivadas , Feminino , Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , RNA-Seq/métodos , Análise de Célula Única/métodos
20.
Development ; 147(7)2020 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-32280064

RESUMO

Understanding the mechanisms that underlie the generation and regeneration of ß cells is crucial for developing treatments for diabetes. However, traditional research methods, which are based on populations of cells, have limitations for defining the precise processes of ß-cell differentiation and trans-differentiation, and the associated regulatory mechanisms. The recent development of single-cell technologies has enabled re-examination of these processes at a single-cell resolution to uncover intermediate cell states, cellular heterogeneity and molecular trajectories of cell fate specification. Here, we review recent advances in understanding ß-cell generation and regeneration, in vivo and in vitro, from single-cell technologies, which could provide insights for optimization of diabetes therapy strategies.


Assuntos
Diferenciação Celular , Linhagem da Célula , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/fisiologia , Regeneração/fisiologia , Análise de Célula Única/métodos , Animais , Rastreamento de Células/métodos , Rastreamento de Células/tendências , Humanos , Pâncreas/citologia , Pâncreas/fisiologia , Análise de Célula Única/tendências
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