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OBJECTIVE: To investigate the value of Dixon magnetic resonance imaging (MRI)-based quantitative parameters of extraocular muscles (EOMs), intraorbital fat (IF), and lacrimal glands (LGs) in staging patients with thyroid-associated ophthalmopathy (TAO). METHODS: Two hundred patients with TAO (211 active and 189 inactive eyes) who underwent Dixon MRI for pretreatment evaluation were retrospectively enrolled and divided into training (169 active and 151 inactive eyes) and validation (42 active and 38 inactive eyes) cohorts. The maximum, mean, and minimum values of the signal intensity ratio (SIR), fat fraction (FF), and water fraction (WF) of EOMs, IF, and LGs were measured and compared between the active and inactive groups in the training cohort. Binary logistic regression analysis, receiver operating characteristic curve analysis, and the Delong test were used for further statistical analyses, as appropriate. RESULTS: Compared with inactive TAOs, active TAOs demonstrated significantly greater EOM-SIRmax, EOM-SIRmean, EOM-SIRmin, IF-SIRmax, IF-SIRmean, LG-SIRmax, LG-SIRmean, EOM-WFmean, EOM-WFmin, IF-WFmax, IF-WFmean, and LG-WFmean and lower EOM-FFmax, EOM-FFmean, IF-FFmean, IF-FFmin, and LG-FFmean values (all p < 0.05). The EOM-SIRmean, LG-SIRmean, and LG-FFmean values were independently associated with active TAO (all p < 0.05). The combination of the EOM-SIRmean, LG-SIRmean, and LG-FFmean values showed better performance than the EOM-SIRmean value alone in staging TAO in both the training (AUC, 0.820 vs 0.793; p = 0.016) and validation (AUC, 0.751 vs 0.733, p = 0.341) cohorts. CONCLUSION: Dixon MRI-based parameters of EOMs, LGs, and IF are useful for differentiating active from inactive TAO. The integration of multiple parameters can further improve staging performance. CRITICAL RELEVANCE STATEMENT: In this study, the authors explored the combined value of quantitative parameters of EOMs, IF, and LGs derived from Dixon MRI in staging TAO patients, which can support the establishment of a proper therapeutic plan. KEY POINTS: The quantitative parameters of EOMs, LGs, and IF are useful for staging TAO. The EOM-SIRmean, LG-SIRmean, and LG-FFmean values were found to independently correlate with active TAO. Joint evaluation of orbital tissue improved the ability to assess TAO activity.
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Temperature is vital in plant growth and agricultural fruit production. Litchi chinensis Sonn, commonly known as litchi, is appreciated for its delicious fruit and fragrant blossoms and is susceptible to stress when exposed to low temperatures. This study investigates the effect of two cryoprotectants that counteract cold stress during litchi flowering, identifies the genes that generate the cold resistance induced by the treatments, and hypothesizes the roles of these genes in cold resistance. Whole plants were treated with Bihu and Liangli cryoprotectant solutions to protect inflorescences below 10 °C. The soluble protein, sugar, fructose, sucrose, glucose, and proline contents were measured during inflorescence. Sucrose synthetase, sucrose phosphate synthetase, antioxidant enzymes (SOD, POD, CAT), and MDA were also monitored throughout the flowering stage. Differentially expressed genes (DEGs), gene ontology, and associated KEGG pathways in the transcriptomics study were investigated. There were 1243 DEGs expressed after Bihu treatment and 1340 in the control samples. Signal transduction pathways were associated with 39 genes in the control group and 43 genes in the Bihu treatment group. The discovery of these genes may contribute to further research on cold resistance mechanisms in litchi. The Bihu treatment was related to 422 low-temperature-sensitive differentially accumulated metabolites (DAMs), as opposed to 408 DAMs in the control, mostly associated with lipid metabolism, organic oxidants, and alcohols. Among them, the most significant differentially accumulated metabolites were involved in pathways such as ß-alanine metabolism, polycyclic aromatic hydrocarbon biosynthesis, linoleic acid metabolism, and histidine metabolism. These results showed that Bihu treatment could potentially promote these favorable traits and increase fruit productivity compared to the Liangli and control treatments. More genomic research into cold stress is needed to support the findings of this study.
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CONTEXT: Dysthyroid optic neuropathy (DON) is a serious vision-threatening complication of thyroid-associated ophthalmopathy (TAO). Exploration of the underlying mechanisms of DON is critical for its timely clinical diagnosis. OBJECTIVE: We hypothesized that TAO patients with DON may have altered brain functional networks. We aimed to explore the alterations of static and dynamic functional connectomes in patients with and without DON using resting-state functional magnetic resonance imaging with the graph theory method. METHODS: A cross-sectional study was conducted at a grade A tertiary hospital with 66 TAO patients (28 DON and 38 non-DON) and 30 healthy controls (HCs). Main outcome measures included topological properties of functional networks. RESULTS: For static properties, DON patients exhibited lower global efficiency (Eg), local efficiency, normalized clustering coefficient, small-worldness (σ), and higher characteristic path length (Lp) than HCs. DON and non-DON patients both exhibited varying degrees of abnormalities in nodal properties. Meanwhile, compared with non-DON, DON patients exhibited abnormalities in nodal properties in the orbitofrontal cortex and visual network (VN). For dynamic properties, the DON group exhibited higher variance in Eg and Lp than non-DON and HC groups. A strengthened subnetwork with VN as the core was identified in the DON cohort. Significant correlations were found between network properties and clinical variables. For distinguishing DON, the combination of static and dynamic network properties exhibited optimal diagnostic performance. CONCLUSION: Functional network alterations were observed both in DON and non-DON patients, providing novel insights into the underlying neural mechanisms of disease. Functional network properties may be potential biomarkers for reflecting the progression of TAO from non-DON to DON.
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Encéfalo , Conectoma , Oftalmopatia de Graves , Imageamento por Ressonância Magnética , Doenças do Nervo Óptico , Humanos , Feminino , Masculino , Estudos Transversais , Oftalmopatia de Graves/complicações , Oftalmopatia de Graves/diagnóstico por imagem , Oftalmopatia de Graves/fisiopatologia , Pessoa de Meia-Idade , Adulto , Doenças do Nervo Óptico/fisiopatologia , Doenças do Nervo Óptico/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Estudos de Casos e Controles , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologiaRESUMO
OBJECTIVES: To evaluate the combined performance of orbital MRI and intracranial visual pathway diffusion kurtosis imaging (DKI) in diagnosing dysthyroid optic neuropathy (DON). METHODS: We retrospectively enrolled 61 thyroid-associated ophthalmopathy (TAO) patients, including 25 with DON (40 eyes) and 36 without DON (72 eyes). Orbital MRI-based apical muscle index (MI), diameter index (DI) of the optic nerve (ON), area index (AI) of the ON, apparent diffusion coefficient (ADC) and signal intensity ratio (SIR) of the ON, DKI-based kurtosis fractional anisotropy (KFA) and mean kurtosis (MK) of the optic tract (OT), optic radiation (OR), and Brodmann areas (BAs) 17, 18, and 19 were measured and compared between groups. The diagnostic performances of models were evaluated using receiver operating characteristic curve analyses and compared using the DeLong test. RESULTS: TAO patients with DON had significantly higher apical MI, apical AI, and SIR of the ON, but significantly lower ADC of the ON than those without DON (p < 0.05). Meanwhile, the DON group exhibited significantly lower KFA across the OT, OR, BA17, BA18, and BA19 and lower MK at the OT and OR than the non-DON group (p < 0.05). The model integrating orbital MRI and intracranial visual pathway DKI parameters performed the best in diagnosing DON (AUC = 0.926), with optimal diagnostic sensitivity (80%) and specificity (94.4%), followed by orbital MRI combination (AUC = 0.890), and then intracranial visual pathway DKI combination (AUC = 0.832). CONCLUSION: Orbital MRI and intracranial visual pathway DKI can both assist in diagnosing DON. Combining orbital and intracranial imaging parameters could further optimize diagnostic efficiency. CLINICAL RELEVANCE STATEMENT: The novel finding could bring novel insights into the precise diagnosis and treatment of dysthyroid optic neuropathy, accordingly, contributing to the improvement of the patients' prognosis and quality of life in the future. KEY POINTS: ⢠Orbital MRI and intracranial visual pathway diffusion kurtosis imaging can both assist in diagnosing dysthyroid optic neuropathy. ⢠Combining orbital MRI and intracranial visual pathway diffusion kurtosis imaging optimized the diagnostic efficiency of dysthyroid optic neuropathy.
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Oftalmopatia de Graves , Doenças do Nervo Óptico , Vias Visuais , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Oftalmopatia de Graves/diagnóstico por imagem , Doenças do Nervo Óptico/diagnóstico por imagem , Vias Visuais/diagnóstico por imagem , Adulto , Imageamento por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Sensibilidade e Especificidade , Nervo Óptico/diagnóstico por imagem , Idoso , Órbita/diagnóstico por imagemRESUMO
OBJECTIVE: To investigate the brain structural and functional alterations in patients with thyroid-associated ophthalmopathy (TAO) before and after glucocorticoid therapy, using voxel-based morphometry (VBM) as well as resting-state functional magnetic resonance imaging (MRI) with amplitude of low-frequency fluctuation (ALFF) and regional homogeneity (ReHo). METHODS: Between 2019 and 2022, 32 patients with TAO and 23 healthy controls underwent pre-therapy MRI in Nanjing, China. Intravenous glucocorticoid therapy was administered to all patients. At 3 months after end of therapy, 26 patients were available for rescanned MRI. VBM, ALFF, and ReHo were used to evaluate the brain structural and functional differences. RESULTS: Before therapy, TAO patients showed significantly decreased gray matter volume (GMV) in the left orbital part of superior frontal gyrus (ORBsup) and medial superior frontal gyrus (SFGmed) than healthy controls. Patients had higher ALFF values in bilateral gyrus rectus and olfactory cortex and lower values in bilateral cuneus. Patients also showed decreased ReHo values in bilateral lingual gyrus. After therapy, increased GMV in the left anterior cingulate gyrus and SFGmed, increased ALFF values in bilateral cuneus and superior occipital gyrus, and increased ReHo values in bilateral SFGmed were found in TAO patients compared to the pre-therapy cohort. Compared to controls, decreased GMV in left ORBsup was observed in post-therapy TAO patients. CONCLUSION: Our results indicated that TAO might cause functional and structural deficits in the visual and emotional regions of the brain, with recovery in the former and partial restoration in the latter after effective glucocorticoid therapy. These findings may lead to deeper understanding of the pathophysiological mechanism behind TAO.
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Glucocorticoides , Oftalmopatia de Graves , Humanos , Glucocorticoides/uso terapêutico , Oftalmopatia de Graves/diagnóstico por imagem , Oftalmopatia de Graves/tratamento farmacológico , Oftalmopatia de Graves/patologia , Encéfalo/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodosRESUMO
Background: To investigate the whole-brain iron deposition alternations in patients with thyroid-associated ophthalmopathy (TAO) using quantitative susceptibility mapping (QSM). Methods: Forty-eight patients with TAO and 33 healthy controls (HCs) were enrolled. All participants underwent brain magnetic resonance imaging scans and clinical scale assessments. QSM values were calculated and compared between TAO and HCs groups using a voxel-based analysis. A support vector machine (SVM) analysis was performed to evaluate the performance of QSM values in differentiating patients with TAO from HCs. Results: Compared with HCs, patients with TAO showed significantly increased QSM values in the bilateral caudate nucleus (CN), left thalamus (TH), left cuneus, left precuneus, right insula and right middle frontal gyrus. In TAO group, QSM values in left TH were positively correlated with Hamilton Depression Rating Scale (HDRS) scores (r = 0.414, p = 0.005). The QSM values in right CN were negatively correlated with Montreal Cognitive Assessment (MoCA) scores (r = -0.342, p = 0.021). Besides that, a nearly negative correlation was found between QSM values in left CN and MoCA scores (r = -0.286, p = 0.057). The SVM model showed a good performance in distinguishing patients with TAO from the HCs (area under the curve, 0.958; average accuracy, 90.1%). Conclusion: Patients with TAO had significantly increased iron deposition in brain regions corresponding to known visual, emotional and cognitive deficits. QSM values could serve as potential neuroimaging markers of TAO.
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Disfunção Cognitiva , Oftalmopatia de Graves , Humanos , Oftalmopatia de Graves/diagnóstico por imagem , Ferro , Encéfalo/diagnóstico por imagem , Mapeamento EncefálicoRESUMO
AIM: To investigate the effect of bicanalicular silicone tube intubation (BSTI) in the treatment of functional epiphora after endoscopic dacryocystorhinostomy (En-DCR). METHODS: Clinical data of 84 patients (95 eyes) with functional epiphora after En-DCR were retrospectively analyzed. Functional epiphora was confirmed as persistent or recurrent epiphora by fluorescein dye disappearance test (FDDT), lacrimal irrigation test, as well as endoscopic examination. Secondary BSTIs were recommended for patients with functional epiphora. These tubes were removed 1mo after surgery. Functional success and associated complications were assessed after 2y of follow-up. RESULTS: Seven patients (9 eyes) refused intervention, 5 patients (6 eyes) did not complete postoperative follow-up, and 1 patient (1 eye) developed tube prolapse within 1mo after surgery. Seventy-one patients (79 eyes) were included at last. Functional success ratios at six months, one year, as well as two years post-operation were 94.9% (75/79), 92.4% (73/79), and 91.1% (72/79), respectively. Three eyes presented with punctal slitting (2 eyes without epiphora), 1 eye with proximal canaliculus slitting, 1 eye with canaliculus stenosis and 4 eyes with still present functional epiphora without detectable abnormal at the last follow-up. CONCLUSION: Secondary intubation is an effective procedure with low recurrence probability for functional epiphora after En-DCR. Punctal and canaliculus injury are the main tube-associated complications after secondary intubation.
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Although previous neuroimaging evidence has confirmed the brain functional disturbances in thyroid-associated ophthalmopathy (TAO), the dynamic characteristics of brain activity and functional connectivity (FC) in TAO were rarely concerned. The present study aims to investigate the alterations of temporal variability of brain activity and FC in TAO using resting-state functional magnetic resonance imaging (rs-fMRI). Forty-seven TAO patients and 30 age-, gender-, education-, and handedness-matched healthy controls (HCs) were enrolled and underwent rs-fMRI scanning. The dynamic amplitude of low-frequency fluctuation (dALFF) was first calculated using a sliding window approach to characterize the temporal variability of brain activity. Based on the dALFF results, seed-based dynamic functional connectivity (dFC) analysis was performed to identify the temporal variability of efficient communication between brain regions in TAO. Additionally, correlations between dALFF and dFC and the clinical indicators were analyzed. Compared with HCs, TAO patients displayed decreased dALFF in the left superior occipital gyrus (SOG) and cuneus (CUN), while showing increased dALFF in the left triangular part of inferior frontal gyrus (IFGtriang), insula (INS), orbital part of inferior frontal gyrus (ORBinf), superior temporal gyrus (STG) and temporal pole of superior temporal gyrus (TPOsup). Furthermore, TAO patients exhibited decreased dFC between the left STG and the right middle occipital gyrus (MOG), as well as decreased dFC between the left TPOsup and the right calcarine fissure and surrounding cortex (CAL) and MOG. Correlation analyses showed that the altered dALFF in the left SOG/CUN was positively related to visual acuity (r = .409, p = .004), as well as the score of QoL for visual functioning (r = .375, p = .009). TAO patients developed abnormal temporal variability of brain activity in areas related to vision, emotion, and cognition, as well as reduced temporal variability of FC associated with vision deficits. These findings provided additional insights into the neurobiological mechanisms of TAO.
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Mapeamento Encefálico , Oftalmopatia de Graves , Humanos , Mapeamento Encefálico/métodos , Oftalmopatia de Graves/diagnóstico por imagem , Qualidade de Vida , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagemRESUMO
Swelling caused by gas generated from municipal solid waste incineration fly ash (MSWIFA) when it is mixed with alkali limits its uses. Besides, the leaching of anion salts and heavy metals contained in MSWIFA poses a high risk to environment. This study presents the feasibility of a one-step alkaline washing, one-step thermal quenching and two-step combination of alkaline washing and thermal quenching pretreatment methods in altering the key properties of MSWIFA for promoting its reusability. It was found that apart from H2(gas), NH3(gas) was also generated during the alkaline washing of the MSWIFA. Besides, pretreatments led to the reduction in particle size, the increase in pore volume and specific surface area of the MSWIFA, as well as the removal of chloride and sulfate anions. All the pretreatment methods were effective in reducing leaching of heavy metals to below levels of nonhazardous waste except Cd and Pb with alkaline washing. Furthermore, both the chemical Frattini test and the mechanical activity index test showed improvement in pozzolanic activities of the MSWIFA after the pretreatments. Overall, the combined pretreatment method was most effective in eliminating gas emission, and reducing leaching of metal ions and anions from the ash, while enhancing the pozzolanic activity of the ash.
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Metais Pesados , Eliminação de Resíduos , Cinza de Carvão/química , Resíduos Sólidos/análise , Incineração , Material Particulado , Carbono/química , Metais Pesados/análiseRESUMO
Besides the well-documented ophthalmic manifestations, thyroid-associated ophthalmopathy (TAO) is believed to be related to emotional and psychological abnormalities. Given the previous neuroimaging evidence, we hypothesized that TAO patients would have altered neurovascular coupling associated with clinical-psychiatric disturbances. This study was to investigate neurovascular coupling changes in TAO by combining resting-state functional magnetic resonance imaging (rs-fMRI) and arterial spin labeling (ASL) techniques. Amplitude of low-frequency fluctuation (ALFF) was calculated from rs-fMRI, and cerebral blood flow (CBF) was computed from ASL in 37 TAO patients and 21 healthy controls (HCs). Global neurovascular coupling was assessed by across-voxel CBF-ALFF correlation, and regional neurovascular coupling was evaluated by CBF/ALFF ratio. Auxiliary analyses were performed using fractional ALFF (fALFF) and regional homogeneity (ReHo) as rs-fMRI measures. Compared with HCs, TAO patients showed significantly reduced global CBF-ALFF coupling. Moreover, TAO patients exhibited decreased CBF/ALFF ratio in the left lingual gyrus (LG)/fusiform gyrus (FFG), and increased CBF/ALFF ratio in the bilateral precuneus (PCu). In TAOs, CBF/ALFF ratio in the left LG/FFG was positively correlated with visual acuity, while CBF/ALFF ratio in the bilateral PCu was negatively correlated with Montreal Cognitive Assessment score. The auxiliary analyses showed trends of reduced global neurovascular coupling (i.e., CBF-fALFF correlation and CBF-ReHo correlation), as well as significant altered regional neurovascular coupling (i.e., CBF/fALFF ratio and CBF/ReHo ratio) in several brain regions. These findings indicated that TAO patients had altered neurovascular coupling in the visual and higher-order cognitive cortices. The neurovascular decoupling might be a possible neuropathological mechanism of TAO.
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Oftalmopatia de Graves , Acoplamento Neurovascular , Humanos , Acoplamento Neurovascular/fisiologia , Imageamento por Ressonância Magnética/métodos , Marcadores de Spin , DescansoRESUMO
AIM: To evaluate the outcome of endoscopic dacryocystorhinostomy (En-DCR) with mucosal anastomosis in chronic dacryocystitis patients, with various categories of ethmoid sinuses. METHODS: Between July 2015 and September 2019, 1439 adult patients, representing 1623 affected eyes, presented with chronic dacryocystitis and were scheduled for En-DCR. The categories of ethmoid sinuses were preoperatively determined, using computed tomography-dacryocystography (CT-DCG), and were classified as category 1 (C1), category 2 (C2), and category 3 (C3). No sinuses anterior to the posterior lacrimal crest defined as C1. Sinuses found between the anterior edge of the lacrimal bone and the posterior lacrimal crest defined as C2. Sinuses found anterior to the lacrimal bone suture defined as C3. At the end of surgery, the dacryocyst and nasal mucosa were anastomosed in C1, and the dacryocyst mucosa and anterior ethmoid sinus were anastomosed in C2 and C3 ethmoid sinus patients. The surgical success rate and related complications, in patients with 3 categories of ethmoid cells, were monitored and documented. RESULTS: Postoperative data was obtained for 179 C1 affected eyes, 878 C2 affected eyes, and 432 C3 affected eyes. The overall success rate of En-DCR was 93.0% (1385/1489). Additionally, the success rates were comparable among the different ethmoid categories at 12mo post operation. We demonstrated that the major reason for surgical failure was intranasal ostial closure, due to granulation or scar tissue. CONCLUSION: En-DCR is a feasible and highly effective primary treatment for chronic dacryocystitis. To ensure surgical success, the surgery protocol must be designed in accordance with the category of ethmoid sinuses present in individual patient.
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Background and Purpose: Although previous neuroimaging studies have demonstrated emotion- and psychology-associated brain abnormalities in patients with thyroid-associated ophthalmopathy (TAO), the changes of brain functional connectivity in TAO were seldom focused. We aimed to investigate interregional and intraregional functional interactions in patients with TAO by using resting-state functional MRI (rs-fMRI) with long- and short-range functional connectivity density (FCD) analysis. Methods: Thirty patients with TAO and 30 well-matched healthy controls (HCs) were recruited in our study. Long- and short-range FCD values were calculated and compared between the two groups. Correlations between long- and short-range FCD values and clinical indicators were analyzed. Results: Compared with HCs, patients with showed both increased long- and short-range FCDs in the left middle frontal gyrus (MFG), orbital part of superior frontal gyrus (ORBsup), and dorsolateral part of superior frontal gyrus (SFGdor); meanwhile, both decreased long- and short-range FCDs in bilateral postcentral gyrus (PoCG), left superior parietal gyrus (SPG), and inferior parietal (IPL). In addition, patients with TAO showed increased short-range FCD in the right SFGdor, bilateral medial part of superior frontal gyrus (SFGmed), left orbital part of middle frontal gyrus (ORBmid), and orbital part of inferior frontal gyrus (ORBinf), as well as decreased short-range FCD in the right supplementary motor area (SMA) and the left paracentral lobule (PCL) than HCs. Moreover, the short-range value in the left SFGdor showed a negative correlation with Montreal Cognitive Assessment (MoCA) score (r = -0.501, p = 0.005). Conclusion: Our findings complemented the functional neural mechanism of TAO, and provided potential neuroimaging markers for assessing the psychiatric, visual, and emotional disturbances in patients with TAO.
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Although current computational biology software is available and has prompted the development of enzyme-substrates simulation, they are difficult to install and inconvenient to use. This makes the time-consuming and error-prone process. By far there is still a lack of a complete tool which can provide a one-stop service for the enzyme-substrates simulation process. Hence, in this study, several computational biology software was extended development and integrated as a website toolbox named Atomevo. The Atomevo is a free web server providing a user-friendly interface for enzyme-substrates simulation: (1) protein homologous modeling; (2) parallel docking module of Autodock Vina 1.2; (3) automatic modeling builder for Gromacs molecular dynamics simulation package; and (4) Molecular Mechanics/Poisson-Boltzmann Surface Area (MMPBSA) analysis module for receptor-ligand binding affinity analysis. We officially launched the web server and provided instructions through a case for the design and simulation of Candida antarctica lipase B (CalB) fusion protein called Maltose Binding Protein-Thioredoxin A-Candida antarctica lipase B (MBP-TrxA-CalB).
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An efficient technique using citric acid and glucose based natural deep eutectic solvent (G-C-NADES) was developed to obtain ultrahigh deamidated wheat gluten (UDWG) (deamidation degree (DD) > 90%). FTIR and 1H NMR indicated intensive hydrogen bonds (HBs) in G-C-NADES supermolecules. Quantum chemical calculations and molecular dynamic simulations demonstrated that 10 wt % diluted G-C-NADES still had a myriad of HBs. Physicochemical results showed UDWG had DD up to 92.45% after G-C-NADES deamidation, that is, 22% higher than citric-acid-DWG with a weak degree of hydrolysis (1.75%). Conformational characterization demonstrated the obvious conversion from α-helix to ß-sheet via FTIR, the least amount of disulfide bonds by Raman spectra, and more exposure of tryptophan residues by fluorescence measurement for UDWG. It is proven that enhanced accessible conformation of WG reached with HBs of G-C-NADESs could contribute to the improvement on nucleophilic attack of deamidation, declaring that G-C-NADES might be a potential solvent for obtaining an ultrahigh deamidation for WG to successfully guarantee the safety of wheat gluten based cereal food regarding to lowering its allergy.
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Ácido Cítrico , Triticum , Glucose , Glutens , SolventesRESUMO
The emergence of worldwide spreading drug-resistant bacteria has been a serious threat to public health during the past decades. The development of new and effective antibacterial agents to address this critical issue is an urgent action. In the present study, we investigated the antibacterial activity of two 9,10-dihydroacridine derivatives and their mechanism. Both compounds were found possessing strong antibacterial activity against some selected Gram-positive bacteria including MRSA, VISA and VRE. The biological study suggests that the compounds promoted FtsZ polymerization and also disrupted Z-ring formation at the dividing site and consequently, the bacterial cell division is interrupted and causing cell death.
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Acridinas/química , Acridinas/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Desenho de Fármacos , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Divisão Celular/efeitos dos fármacos , Proteínas do Citoesqueleto/antagonistas & inibidores , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/metabolismo , Bactérias Gram-Positivas/efeitos dos fármacos , Meticilina/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacosRESUMO
This paper investigates the conformational stability of porcine pancreatic lipase (PPL) in three non-aqueous organic solvents, including dimethyl sulfoxide (DMSO), propylene glycol (PRG), and ethanol (EtOH) through molecular dynamic (MD) simulation. The root mean square deviations (RMSDs), radius of gyration (Rg), solution accessible surface area (SASA), radial distribution function (RDF), hydrogen bond (H-bond), Ramachandran plot analysis, secondary structure, and enzyme substrate affinity of the PPL in the various organic solvents were comparatively investigated. The results showed that the backbone and active pocket RMSD, and hydrophilic ASA of PPL in three solvents increase with the increase in the solvent LogP, while the Rg, hydrophobic ASA, and H-bond between the solvent and PPL decrease. Among the three organic solvents, DMSO acts as a better solvent, in which the PPL can be loose and extended, and retains its native backbone in DMSO compared to PRG and EtOH. Moreover, Ramachandran plot analysis indicated that the PPL structure quality in DMSO was higher than that in PRG and EtOH. Also, the molecular docking results showed that PPL in DMSO exhibited the highest enzyme-substrate affinity.
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High-frequency gating InGaAs/InP single-photon detectors (SPDs) are widely used for applications requiring single-photon detection in the near-infrared region such as quantum key distribution. Reducing SPD size is highly desired for practical use, which is favorable to the implementation of further system integration. Here we present, to the best of our knowledge, the most compact high-frequency sine wave gating (SWG) InGaAs/InP SPD. We design and fabricate an InGaAs/InP single-photon avalanche diode (SPAD) with optimized semiconductor structure and then encapsulate the SPAD chip and a mini-thermoelectric cooler inside a butterfly package with a size of 12.5 mm × 22 mm × 10 mm. Moreover, we implement a monolithic readout circuit for the SWG SPD in order to replace the quenching electronics that is previously designed with board-level integration. Finally, the components of SPAD, the monolithic readout circuit, and the affiliated circuits are integrated into a single module with a size of 13 cm × 8 cm × 4 cm. Compared with the 1.25 GHz SWG InGaAs/InP SPD module (25 cm × 10 cm × 33 cm) designed in 2012, the volume of our miniaturized SPD is reduced by 95%. After the characterization, the SPD exhibits excellent performance with a photon detection efficiency of 30%, a dark count rate of 2.0 kcps, and an afterpulse probability of 8.8% under the conditions of 1.25 GHz gating rate, 100 ns hold-off time, and 243 K. Also, we perform the stability test over one week, and the results show the high reliability of the miniaturized SPD module.
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InGaAs/InP single-photon detectors (SPDs) are the key devices for applications requiring near-infrared single-photon detection. The gating mode is an effective approach to synchronous single-photon detection. Increasing gating frequency and reducing the module size are important challenges for the design of such a detector system. Here we present for the first time, to the best of our knowledge, an InGaAs/InP SPD with 1.25 GHz sine wave gating (SWG) using a monolithically integrated readout circuit (MIRC). The MIRC has a size of 15 mm×15 mm and implements the miniaturization of avalanche extraction for high-frequency SWG. In the MIRC, low-pass filters and a low-noise radio frequency amplifier are integrated based on the technique of low temperature co-fired ceramic, which can effectively reduce the parasitic capacitance and extract weak avalanche signals. We then characterize the InGaAs/InP SPD to verify the functionality and reliability of the MIRC, and the SPD exhibits excellent performance with 27.5% photon detection efficiency, a 1.2 kcps dark count rate, and 9.1% afterpulse probability at 223 K and 100 ns hold-off time. With this MIRC, one can further design miniaturized high-frequency SPD modules that are highly required for practical applications.
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Silicon single-photon detectors (SPDs) are the key devices for detecting single photons in the visible wavelength range. Here we present high detection efficiency silicon SPDs dedicated to the generation of multiphoton entanglement based on the technique of high-frequency sine wave gating. The silicon single-photon avalanche diode components are acquired by disassembling 6 commercial single-photon counting modules (SPCMs). Using the new quenching electronics, the average detection efficiency of SPDs is increased from 68.6% to 73.1% at a wavelength of 785 nm. These sine wave gating SPDs are then applied in a four-photon entanglement experiment, and the four-fold coincidence count rate is increased by 30% without degrading its visibility compared with the original SPCMs.