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1.
Molecules ; 29(13)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38998951

RESUMO

In our search for a biocompatible composite hemostatic dressing, we focused on the design of a novel biomaterial composed of two natural biological components, collagen and sodium alginate (SA), cross-linked using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) and oxidized sodium alginate (OSA). We conducted a series of tests to evaluate the physicochemical properties, acute systemic toxicity, skin irritation, intradermal reaction, sensitization, cytotoxicity, and in vivo femoral artery hemorrhage model. The results demonstrated the excellent biocompatibility of the collagen/sodium alginate (C/SA)-based dressings before and after crosslinking. Specifically, the femoral artery hemorrhage model revealed a significantly shortened hemostasis time of 132.5 ± 12.82 s for the EDC/NHS cross-linked dressings compared to the gauze in the blank group (hemostasis time of 251.43 ± 10.69 s). These findings indicated that C/SA-based dressings exhibited both good biocompatibility and a significant hemostatic effect, making them suitable for biomedical applications.


Assuntos
Alginatos , Bandagens , Colágeno , Hemostáticos , Alginatos/química , Alginatos/farmacologia , Animais , Colágeno/química , Colágeno/farmacologia , Hemostáticos/química , Hemostáticos/farmacologia , Camundongos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Teste de Materiais , Hemorragia/tratamento farmacológico , Masculino , Ratos , Hemostasia/efeitos dos fármacos , Artéria Femoral
2.
Cell Mol Biol (Noisy-le-grand) ; 69(6): 75-81, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37605588

RESUMO

This study was to observe the effect of Sodium TanshinoneⅡA Sulfonate (ST-ⅡAS) on blood uric acid (UA), human Soluble Intercellular Adhesion Molecule-1 (sICAM-1), Endothelin-1 (ET-1) and percentage of brachial artery Flow-Mediated Dilatation (FMD) in individuals with Hyperuricemia Complicated Coronary Heart Disease (HC-CHD). The study's participants were 108 patients with HC-CHD who attended our hospital between January 2020 and June 2022. In the trial, the patients were split into two groups with 54 instances each: the general group and the observation group. The observation group received ST-IIAS therapy, while the general group received standard care. The experiment chose to observe and compare the difference of uric acid, sICAM-1, ET-1, FMD, therapeutic effectiveness and negative effects between the two groups at various times. Results showed that on the 14th day, the observation group's amounts of UA, sICAM-1, and ET-1 were inferior to the general group (P<0.05); On the 7th and 14th days, the observation group's amount of ET-1 was lower than that of the general group (P<0.05); The observation group's FMD of patients on the 14th day was inferior to the general group after treatment (P<0.05); The observation group's overall effective rate was 94.44% higher than the general group's (P<0.05); The observation group experienced fewer negative responses than the general group did (P<0.05). In conclusion, ST-ⅡAS can be used for uric acid, vascular endothelial systolic and diastolic function in patients with HC-CHD, and has better clinical efficacy and lower risk of adverse reactions.


Assuntos
Doença das Coronárias , Hiperuricemia , Humanos , Endotelina-1 , Ácido Úrico , Hiperuricemia/complicações , Hiperuricemia/tratamento farmacológico , Dilatação , Alcanossulfonatos
3.
BMC Anesthesiol ; 23(1): 299, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37670239

RESUMO

BACKGROUND: Postoperative cognitive dysfunction (POCD) has been reported as a significant complication in elderly patients. Various methods have been proposed for reducing the incidence and severity of POCD. Intravenous lidocaine administration has been reported in the literature to reduce POCD, but the effect of lidocaine remains controversial. METHODS: We screened Medline, Embase, Cochrane Library, and China National Knowledge Infrastructure (up to April 2022) databases following a search strategy for intravenous lidocaine on POCD. We also screened related bibliographies on lidocaine for POCD. Ten articles comprising 1517 patients were selected and analyzed. We divided the postoperative follow-up period as follows: short term (<30 days), medium term (30-90 days), and long term (>90 days). OUTCOMES: We found that lidocaine could attenuate the overall incidence of POCD, especially in the short term. There were no differences between lidocaine and placebo on the overall severity of POCD. CONCLUSION: Lidocaine administered intravenously could attenuate the overall incidence of POCD and its severity in the short term.


Assuntos
Complicações Cognitivas Pós-Operatórias , Idoso , Humanos , Administração Intravenosa , China , Bases de Dados Factuais , Lidocaína
4.
Mar Drugs ; 21(7)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37504926

RESUMO

The study aimed to investigate the effects of alcalase, papain, flavourzyme, and neutrase on the structural characteristics and bioactivity stability of Cucumaria frondosa intestines and ovum hydrolysates (CFHs). The findings revealed that flavourzyme exhibited the highest hydrolysis rate (51.88% ± 1.87%). At pH 2.0, the solubility of hydrolysate was the lowest across all treatments, while the solubility at other pH levels was over 60%. The primary structures of hydrolysates of different proteases were similar, whereas the surface hydrophobicity of hydrolysates was influenced by the types of proteases used. The hydrolysates produced by different proteases were also analyzed for their absorption peaks and antioxidant activity. The hydrolysates of flavourzyme had ß-fold absorption peaks (1637 cm-1), while the neutrase and papain hydrolysates had N-H bending vibrations. The tertiary structure of CFHs was unfolded by different proteases, exposing the aromatic amino acids and red-shifting of the λ-peak of the hydrolysate. The alcalase hydrolysates showed better antioxidant activity in vitro and better surface hydrophobicity than the other hydrolysates. The flavourzyme hydrolysates displayed excellent antioxidant stability and pancreatic lipase inhibitory activity during gastrointestinal digestion, indicating their potential use as antioxidants in the food and pharmaceutical industries.


Assuntos
Cucumaria , Peptídeo Hidrolases , Animais , Peptídeo Hidrolases/metabolismo , Papaína/química , Antioxidantes/farmacologia , Hidrólise , Intestinos , Subtilisinas/química , Hidrolisados de Proteína/química
5.
Inflammopharmacology ; 31(5): 2237-2244, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37418101

RESUMO

The inflammatory response is responsible for the promotion of pannus development over the joint, which is the primary factor in joint injury in rheumatoid arthritis (RA). More in-depth investigations have been conducted in recent years leading to a greater understanding of RA. Yet, it's difficult to gauge inflammation levels in RA patients. Some people who have RA do not exhibit normal symptoms, which makes it more challenging to make a diagnosis. Typical RA evaluations are subject to a few restrictions. Earlier research demonstrated that some patients continued to experience the progression of bone and joint degeneration even while in clinical remission. This progression was attributed to ongoing synovial inflammation. As a result, performing a precise evaluation of the level of inflammation is of the utmost importance. The neutrophil-to-lymphocyte ratio (NLR) has consistently been one of the most interesting novel non-specific inflammatory indicators. It is a reflection of the equilibrium between lymphocytes and neutrophils, which are inflammatory regulators and inflammatory activators, respectively. A higher NLR is linked to more severe levels of imbalance and inflammation. The aim of this study was to depict the role of NLR in RA progression and to show if NLR could predict the response to disease-modifying antirheumatic drugs (DMARDs) therapy in RA.


Assuntos
Antirreumáticos , Artrite Reumatoide , Humanos , Neutrófilos , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/diagnóstico , Linfócitos , Antirreumáticos/uso terapêutico , Inflamação/tratamento farmacológico
6.
BMC Vet Res ; 18(1): 392, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36348321

RESUMO

BACKGROUND: Porcine epidemic diarrhea virus (PEDV), an enteric coronavirus, has become the major causative agent of acute gastroenteritis in piglets since 2010 in China. RESULTS: In the current study, 91 complete spike (S) gene sequences were obtained from PEDV positive samples collected from 17 provinces in China from March 2020 to March 2021. A phylogenetic analysis showed that 92.3% (84 out of 91) of the identified strains belonged to GII subtype, while 7.7% (7 out of 91) were categorized as S-INDEL like strains and grouped within GI-c clade. Based on a recombination analysis, six of S-INDEL like strains were recombinant strains originated from S-INDEL strain FR/001/2014 and virulent strain AJ1102. In addition, PEDV variant strains (CH/GDMM/202012, CH/GXDX/202010 et al) carrying novel insertions (360QGRKS364 and 1278VDVF1281) in the S protein were observed. Furthermore, the deduced amino acid sequences for the S protein showed that multiple amino acid substitutions in the antigenic epitopes in comparison with the vaccine strains. CONCLUSIONS: In conclusion, these data provide novel molecular evidence on the epidemiology and molecular diversity of PEDV in 2020-2021. This information may help design a strategy for controlling and preventing the prevalence of PEDV variant strains in China.


Assuntos
Infecções por Coronavirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Animais , Suínos , Filogenia , Doenças dos Suínos/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Sequência de Aminoácidos , China/epidemiologia , Glicoproteína da Espícula de Coronavírus/genética
7.
J Tissue Viability ; 31(1): 180-189, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34538555

RESUMO

AIM OF THE STUDY: The aim of the study was to fabricate collagen-based composite dressings, evaluate the efficiency for wound healing and reveal the mechanism of promoting wound healing. MATERIALS AND METHODS: An innovative bi-layered composite wound dressing was developed using two marine biomacromolecules (collagen and chitosan). Full-thickness skin defect model was performed to evaluate the wound healing activity in vivo. The levels of inflammatory cytokines including tumor necrosis factor alpha (TNF-α), interleukin (IL-1, IL-6, IL-8) and growth factors like transforming growth factor beta (TGF-ß), vascular epidermal growth factor (VEGF) and basic fibroblast growth factor (bFGF) were quantified by ELISA assays. The total amount of collagen was quantified by hydroxyproline content. The proliferation and viability of fibroblast cells cultured on collagen sponges were determined by CCK-8 assay. RESULTS: The results of wound closure and histopathological analysis indicated that non-crosslinked collagen-based bi-layered composite dressing stimulated wound healing, accelerated re-epithelialization and accomplished wound healing within a time span of 28 days. The results of levels of inflammatory cytokines and growth factors showed that collagen-based composite dressings could reduce the inflammatory response and upregulate growth factors levels to accelerate the wound healing. The results of hydroxyproline content and CCK-8 assay indicated that collagen-based composite dressings could also promote collagen synthesis and fibroblasts viability and proliferation. CONCLUSION: The non-crosslinked collagen-based bi-layered composite dressing could be applied for an efficient and ideal wound dressing. Therefore, the findings provided the essential theoretical basis for the potential of collagen-based composite dressing applied in wound healing fields.


Assuntos
Bandagens , Cicatrização , Colágeno , Reepitelização , Pele
8.
J Tissue Viability ; 30(3): 454-461, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33962852

RESUMO

AIM OF THE STUDY: The aim of the current study was to develop collagen-based bi-layered composite dressings with antibacterial property and evaluate the efficiency for wound healing. MATERIALS AND METHODS: A bi-layered composite wound dressing was fabricated using two marine biomacromolecules (collagen and chitosan or carboxymethyl chitosan). Non-crosslinked and N-Ethyl-N'-(3-dimethylaminopropyl) carbodiimide/N-Hydroxy succinimide (EDC/NHS) cross-linked collagen sponges fabricated by vacuum freeze-drying technology was used as the inner layer. The medical spun-laced nonwoven coated with chitosan and carboxymethyl chitosan was used as the outer layer. The antibacterial activities against E. coli and S. aureus were evaluated by the inhibition zone assay. Deep second-degree scald model was performed to evaluate the efficiency of bi-layered composite dressings for wound healing. RESULTS: In view of comprehensive evaluation of appearance and in vitro antibacterial activity, medical spun-laced nonwoven coated with 3% of chitosan solution was chosen to be used as the optimized preparation conditions to produce the outer layer of composite dressing, which acted as a barrier against microorganisms and provided mechanical support. Furthermore, the results of wound closure and histopathological analysis indicated that EDC/NHS cross-linked collagen-based bi-layered composite dressing was superior to non-crosslinked and commercial products, which stimulated the wound healing process and accomplished deep second-degree scalded skin healing within a time span of 28 days. CONCLUSION: The EDC/NHS cross-linked collagen-based bi-layered composite dressing had immense potential to be applied for an ideal wound dressing for more efficient and faster wound healing. Therefore, the findings provided the essential theoretical basis for great potential of collagen-based composite dressing used in wound healing applications.


Assuntos
Antibacterianos/normas , Bandagens/normas , Colágeno/farmacologia , Cicatrização/efeitos dos fármacos , Análise de Variância , Animais , Antibacterianos/administração & dosagem , Bandagens/estatística & dados numéricos , Colágeno/uso terapêutico , Modelos Animais de Doenças , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
9.
Mar Drugs ; 17(3)2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30813606

RESUMO

The aim of this study is to investigate the physicochemical properties, biosafety, and biocompatibility of the collagen extract from the skin of Nile tilapia, and evaluate its use as a potential material for biomedical applications. Two extraction methods were used to obtain acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) from tilapia skin. Amino acid composition, FTIR, and SDS-PAGE results showed that ASC and PSC were type I collagen. The molecular form of ASC and PSC is (α1)2α2. The FTIR spectra of ASC and PSC were similar, and the characteristic peaks corresponding to amide A, amide B, amide I, amide II, and amide III were 3323 cm-1, 2931 cm-1, 1677 cm-1, 1546 cm-1, and 1242 cm-1, respectively. Denaturation temperatures (Td) were 36.1 °C and 34.4 °C, respectively. SEM images showed the loose and porous structure of collagen, indicting its physical foundation for use in applications of biomedical materials. Negative results were obtained in an endotoxin test. Proliferation rates of osteoblastic (MC3T3E1) cells and fibroblast (L929) cells from mouse and human umbilical vein endothelial cells (HUVEC) were increased in the collagen-treated group compared with the controls. Furthermore, the acute systemic toxicity test showed no acute systemic toxicity of the ASC and PSC collagen sponges. These findings indicated that the collagen from Nile tilapia skin is highly biocompatible in nature and could be used as a suitable biomedical material.


Assuntos
Materiais Biocompatíveis/química , Ciclídeos , Colágeno Tipo I/química , Proteínas de Peixes/química , Animais , Materiais Biocompatíveis/isolamento & purificação , Linhagem Celular , Colágeno Tipo I/isolamento & purificação , Colágeno Tipo I/ultraestrutura , Proteínas de Peixes/isolamento & purificação , Proteínas de Peixes/ultraestrutura , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Microscopia Eletrônica de Varredura , Pele/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Mikrochim Acta ; 186(8): 502, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31270621

RESUMO

The balance between free oxygen radicals and antioxidant defense systems is usually assessed by an antioxidant capacity assay. A rapid and sensitive antioxidant capacity assay is described here. It is making use of NaYF4:Yb/Er@NaYF4 core-shell upconversion nanoparticles (UCNPs) and potassium permanganate (KMnO4). In this strategy, added KMnO4 reduces the green (540 nm) emission of the UCNPs (under 980 nm photoexcitation) due to an inner filter effect. The antioxidants cysteine, ascorbic acid and glutathione (GSH) reduce the intense purple color of KMnO4 because it is reduced to Mn(II) ion. Hence, the green upconversion fluorescence is restored after the addition of antioxidants. Figures of merit for this assay (for the case of GSH) include a detection limit of 3.3 µM, a detection range that extends from 10 µM to 2.5 mM, and an assay time of a few seconds. The assay was applied to the evaluation of antioxidant capacity in human plasma samples spiked with GSH and gave satisfactory repeatability and specificity. Graphical abstract Schematic presentation of a fluorometric assay based on inner filter effect (IFE) between upconversion nanoparticles (UCNPs) and potassium permanganate (KMnO4) for the determination of antioxidant capacity in human plasma.


Assuntos
Ácido Ascórbico/análise , Cisteína/análise , Érbio/química , Fluoretos/química , Glutationa/análise , Nanopartículas/química , Permanganato de Potássio/química , Itérbio/química , Ítrio/química , Ácido Ascórbico/sangue , Ácido Ascórbico/química , Técnicas Biossensoriais , Cisteína/química , Fluorometria , Glutationa/sangue , Glutationa/química , Humanos
11.
J Biomed Inform ; 83: 178-195, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29902575

RESUMO

BACKGROUND: A clinical pathway (CP) defines a standardized care process for a well-defined patient group that aims to improve patient outcomes and promote patient safety. However, the construction of a new pathway from scratch is a time-consuming task for medical staff because it involves many factors, including objects, multidisciplinary collaboration, sequential design, and outcome measurements. Recently, the rapid development of hospital information systems has allowed the storage of large volumes of electronic medical records (EMRs), and this information constitutes an abundant data resource for building CPs using data-mining methods. METHODS: We provide an automatic method for extracting typical treatment processes from EMRs that consists of four key steps. First, a novel similarity method is proposed to measure the similarity of two treatment records. Then, we perform an affinity propagation (AP) clustering algorithm to cluster doctor order set sequences (DOSSs). Next, a framework is proposed to extract a high-level description of each treatment cluster. Finally, we evaluate the extracted typical treatment processes by matching the treatment cluster with external information, such as the treatment efficacy, length of stay, and treatment cost. RESULTS: By experiments on EMRs of 8287 cerebral infarction patients, it is concluded that our proposed method can effectively extract typical treatment processes from treatment records, and also has great potential to improve treatment outcome by personalizing the treatment process for patients with different conditions. CONCLUSION: The extracted typical treatment processes are intuitive and can provide managerial guidance for CP redesign and optimization. In addition, our work can assist clinicians in clearly understanding their routine treatment processes and recommend optimal treatment pathways for patients.


Assuntos
Análise por Conglomerados , Procedimentos Clínicos , Mineração de Dados , Registros Eletrônicos de Saúde , Algoritmos , Infarto Cerebral/terapia , Humanos
12.
Zhongguo Zhong Yao Za Zhi ; 43(3): 618-626, 2018 Feb.
Artigo em Zh | MEDLINE | ID: mdl-29600631

RESUMO

Under the theoretical guidance of "combination of disease and syndrome, correspondence between syndrome and prescription, and dynamic space-time", 11 135 acute ischemic stroke patients were collected from hospital information system(HIS) of many 3A grade hospitals of traditional Chinese medicine. Complex network analysis was adopted to obtain the core syndrome elements in different periods of acute ischemic stroke patients, and it was found that the core syndrome elements were blood stasis syndrome, phlegm, endogenous wind, Yin deficiency, Qi deficiency, heat, hyperactivity of liver Yang, liver, and kidney of patients in hospital for the first day, and during 8-14 d in hospitalization, the core syndrome elements were blood stasis, phlegm, Yin deficiency, Qi deficiency, endogenous wind, hyperactivity of liver Yang, liver, and kidney. The data with "improved" and "cured" treatment outcomes were adopted for complex network analysis and correlation analysis to identify the Chinese and Western medicine group modules in patients with different disease conditions in different phases after hospitalization. It was found that the Chinese and Western medicine modules within 14 d after hospitalization mainly included "blood-activating and stasis-dissolving module "consisted by "anti-platelet drug + circulation-improving medicine(or anticoagulant drug and anti-fibrinogen drug, et al) + blood-activating and stasis-dissolving drugs", as well as "stasis-dissolving and phlegm-reducing module" consisted by "anti-platelet drugs + circulation-improving medicine(or anticoagulant drug and anti-fibrinogen drug, et al) + phlegm refreshing drug". The core Chinese and Western medicine modules in patients with urgent and general conditions within 7 d after hospitalization mainly used "blood-activating and stasis-dissolving module" and "stasis-dissolving and phlegm-reducing module". Three or more Chinese medicine and Western medicines module with more than 1% utilization rate was not found in the patients with critical disease condition in admission. The urgent, general and critically ill patients in admission mainly used "blood-activating and stasis-dissolving module" in 8-14 d. From the real world medical big data research, it was found that the combined use of Chinese and Western medicines were consistent with "combination of disease and syndrome, correspondence between syndrome and prescription, and dynamic space-time" theory, and multiple multidimensional dynamic Chinese medicine and Western medicine group modules of "patient-syndrome-drug-time-effective" at the acute ischemic stroke stage were dug out, forming the method of Chinese and Western medicine combination research based on electrical medical big data.


Assuntos
Isquemia Encefálica/diagnóstico , Isquemia Encefálica/terapia , Medicina Tradicional Chinesa , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Humanos , Síndrome , Deficiência da Energia Yin
13.
Zhongguo Zhong Yao Za Zhi ; 40(24): 4783-90, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-27245023

RESUMO

The acute phase of ischemic stroke patients are often treated with both Chinese patent medicine:and western medicine therapies in clinical practice. This research included 27,678 cases of the acute phase of ischemic stroke came from 14 3A level hospitals. We collected data from patients with ischemic stroke who used both Chinese patent medicine and western medicine and were hopitalized within 14 days from hospital information system (HIS). Constructing complex network of Chinese patent medicine and western medicine were found to show scale-free network. Hierarchical structure of the core algorithm was used to analyze the characteristics of combined core Chinese patent medicine and western medicine in admission condition of "acute", "critically", and "general" of ischemic stroke acute phase patient within one day, 2-3 days, 4-7 days and 8-14 days. We found that the core Chinese patent medicine mainly used for activate blood and resolve stasis medicine, and phlegm eliminating brain refreshing medicine in all kinds of patients, but the phlegm eliminating brain refreshing medicine were used to reduce with time elapsing. The core western medicine mainly used for anti-platelet medicine, improve circulation medicine, neuroprotective medicine, anticoagulants medicine and dehydration medicine. The dehydration medicine as the core western medicine for critically patients within 14 days, but the patients for general admission as core western medicine within 3 days. The neuroprotective medicine was used to decreases after 7 days in hospital. Combination of Chinese patent medicine and western medicine were mainly for neuroprotective medicine + activate blood and resolve stasis medicine, and anti-platelet medicine + activate blood and resolve stasis medicine, and improve circulation medicine + activate blood and resolve stasis medicine. The phlegm eliminating brain refreshing medicine was mainly combined with neuroprotective medicine by urgent and general admission condition patients, and it was more combined with dehydration medicine by critically admission condition patients. This research found that the dynamic characteristics for the combination of Chinese patent medicine and western medicine of acute phase of ischemic stroke patients by big data analytics and complex networks modeling, and provide basis for acute phase of ischemic stroke patients, it provide basis for ischemic stroke treatment strategy making.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Medicina Tradicional Chinesa , Acidente Vascular Cerebral/tratamento farmacológico , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Appl Opt ; 53(31): 7369-80, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25402902

RESUMO

A uniform plano-convex spherical microlens array with a long focal length was fabricated by combining the micromilling and injection molding processes in this work. This paper presents a quantitative study of the injection molding process parameters on the uniformity of the height of the microlenses. The variation of the injection process parameters, i.e., barrel temperature, mold temperature, injection speed, and packing pressure, was found to have a significant effect on the uniformity of the height of the microlenses, especially the barrel temperature. The filling-to-packing switchover point is also critical to the uniformity of the height of the microlenses. The optimal uniformity was achieved when the polymer melts completely filled the mold cavity, or even a little excessively filled the cavity, during the filling stage. In addition, due to the filling resistance, the practical filling-to-packing switchover point can vary with the change of the filling processing conditions and lead to a non-negligible effect on the uniformity of the height of the microlenses. Furthermore, the effect of injection speed on the uniformity of the height of the microlenses was analyzed in detail. The results indicated that the effect of injection speed on the uniformity of the height of the microlenses is mainly attributed to the two functions of injection speed: transferring the filling-to-packing switchover point and affecting the distribution of residual flow stress in the polymer melt.


Assuntos
Lentes , Microfluídica/instrumentação , Polimetil Metacrilato/química , Desenho de Equipamento , Análise de Falha de Equipamento , Miniaturização
15.
IEEE Trans Neural Netw Learn Syst ; 35(9): 11857-11871, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38976472

RESUMO

Designing new molecules is essential for drug discovery and material science. Recently, deep generative models that aim to model molecule distribution have made promising progress in narrowing down the chemical research space and generating high-fidelity molecules. However, current generative models only focus on modeling 2-D bonding graphs or 3-D geometries, which are two complementary descriptors for molecules. The lack of ability to jointly model them limits the improvement of generation quality and further downstream applications. In this article, we propose a joint 2-D and 3-D graph diffusion model (JODO) that generates geometric graphs representing complete molecules with atom types, formal charges, bond information, and 3-D coordinates. To capture the correlation between 2-D molecular graphs and 3-D geometries in the diffusion process, we develop a diffusion graph transformer (DGT) to parameterize the data prediction model that recovers the original data from noisy data. The DGT uses a relational attention mechanism that enhances the interaction between node and edge representations. This mechanism operates concurrently with the propagation and update of scalar attributes and geometric vectors. Our model can also be extended for inverse molecular design targeting single or multiple quantum properties. In our comprehensive evaluation pipeline for unconditional joint generation, the experimental results show that JODO remarkably outperforms the baselines on the QM9 and GEOM-Drugs datasets. Furthermore, our model excels in few-step fast sampling, as well as in inverse molecule design and molecular graph generation. Our code is provided in https://github.com/GRAPH-0/JODO.

16.
Polymers (Basel) ; 16(2)2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38256970

RESUMO

(1) Background: Collagen and sodium alginate are commonly used in the field of biomedical materials due to their excellent biocompatibility. This study focuses on the preparation, modification, and characterization of collagen/sodium alginate (C/SA)-based biomedical materials. (2) Methods: The characteristics, including surface chemistry, mechanical properties, hygroscopicity, and porosity, were analyzed. The hemostatic activity in vitro was measured using a blood clotting assay and dynamic blood clotting assay. (3) Results: The results from microstructure and porosity measurement revealed that all of the sponges exhibited a porosity of more than 95 percent. The sponge cross-linked with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) showed better tensile strength and lower elongation at break. The sponges cross-linked with EDC/NHS and oxidized sodium alginate (OSA) exhibited the highest hygroscopicity in comparison with the uncross-linked sponge. (4) Conclusions: Our study demonstrated that the C/SA-based material we prepared exhibited a high level of porosity, enabling efficient absorption of tissue exudate and blood. Additionally, the materials revealed excellent hemocompatibility, making them suitable for use as a hemostatic dressing in the field of biomedical materials.

17.
Int J Biol Macromol ; 262(Pt 1): 130069, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340918

RESUMO

Squid pen (SP) is a valuable source of protein and ß-chitin. However, current research has primarily focused on extracting ß-chitin from SP. This study innovatively extracted both SP protein hydrolysates (SPPHs) and SP ß-chitin (SPC) simultaneously using protease hydrolysis. The effects of different proteases on their structural characteristics and bioactivity were evaluated. The results showed that SP alcalase ß-chitin (SPAC) had the highest degree of deproteinization (DP, 98.19 %) and SP alcalase hydrolysates (SPAH) had a degree of hydrolysis (DH) of 24.47 %. The analysis of amino acid composition suggested that aromatic amino acids accounted for 17.44 % in SPAH. Structural characterization revealed that SP flavourzyme hydrolysates (SPFH) had the sparsest structure. SPC exhibited an excellent crystallinity index (CI, over 60 %) and degree of acetylation (DA, over 70 %). During simulated gastrointestinal digestion (SGD), the hydroxyl radical scavenging activity, ABTS radical scavenging activity, Fe2+ chelating activity, and reducing power of the SPPHs remained stable or increased significantly. Additionally, SPFC exhibited substantial inhibitory effects on Staphylococcus aureus and Escherichia coli (S. aureus and E. coli), with inhibition circle diameters measuring 2.4 cm and 2.1 cm. These findings supported the potential use of SPPHs as natural antioxidant alternatives and suggested that SPC could serve as a potential antibacterial supplement.


Assuntos
Peptídeo Hidrolases , Hidrolisados de Proteína , Animais , Peptídeo Hidrolases/metabolismo , Hidrólise , Hidrolisados de Proteína/química , Decapodiformes/química , Quitina , Escherichia coli/metabolismo , Staphylococcus aureus/metabolismo , Antioxidantes/química , Subtilisinas/metabolismo
18.
Anal Chim Acta ; 1320: 342992, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39142769

RESUMO

Hydrogen sulfide (H2S) is a poisonous pollutant that endangers the environment, and H2S is also produced during food spoilage. Herein, we constructed a dicyanoisophorone-based near-infrared (NIR) fluorescent probe (DCID) to detect H2S. DCID exhibited significant turn-on fluorescence at 700 nm with a low limit of detection (LOD = 74 nM), large Stokes shift (220 nm), prominent selectivity, and response time (100 s) toward H2S. Importantly, the DCID probe had powerful applications in the detection of H2S in environmental samples and food spoilage. In addition, based on DCID-loaded test strips and combined a smartphone sensing platform, which provided a portable and convenient approach for the detection of H2S.


Assuntos
Corantes Fluorescentes , Sulfeto de Hidrogênio , Sulfeto de Hidrogênio/análise , Corantes Fluorescentes/química , Limite de Detecção , Contaminação de Alimentos/análise , Espectrometria de Fluorescência , Poluentes Químicos da Água/análise , Raios Infravermelhos
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124341, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38676987

RESUMO

Hydrogen sulfide (H2S) is a common toxic gas that threatens the quality and safety of environmental water and food. Herein, a new near-infrared fluorescent probe DTCM was synthesized and characterized by single crystal X-ray diffraction for sensing H2S. It exhibited a remarkable "turn-on" near-infrared (NIR) emission response at 665 nm with a remarkably massive Stokes shift of 175 nm, super-rapid detection ability (within 30 s), excellent photostability, high selectivity and sensitivity (limit of detection, LOD = 58 nM). Additionally, the probe was successfully utilized for the detection of H2S in environmental water samples. The DTCM-loaded test papers enabled convenient and real-time monitoring of H2S produced by food spoilage.


Assuntos
Corantes Fluorescentes , Sulfeto de Hidrogênio , Limite de Detecção , Espectrometria de Fluorescência , Água , Sulfeto de Hidrogênio/análise , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Água/química , Contaminação de Alimentos/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Análise de Alimentos/métodos , Poluentes Químicos da Água/análise
20.
ACS Nano ; 18(35): 24350-24363, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39163088

RESUMO

The uncontrollable dendrite growth and complex parasitic reactions of Zn metal anodes cause short cycle lives and low Coulombic efficiency, which seriously affect their applications. To address these issues, this research proposes an efficient ion percolating interface constituted by a hydrogen-bonded organic framework (HND) for a highly stable and reversible Zn anode. The hydrogen-bonded skeleton acts as a molecular filter net, capturing water molecules by forming targeted hydrogen-bonding systems with them, sufficiently inhibiting parasitic reactions. Additionally, the interaction of the rich-N and -O electrochemically active sites with Zn2+ effectively regulates its percolation, which greatly enhances the diffusion kinetics of Zn2+, thus facilitating rapid and uniform migration of Zn2+ at the anode surface. Through the above synergistic effect, dendrite-free anodes with highly reversible Zn plating/stripping behaviors can be achieved. Hence, the modified Zn anode (HND@Zn) performs a steady cycling time of more than 1700 h at 1 mA cm-2. Moreover, the HND@Cu||Zn asymmetric cell exhibits a stable charge/discharge process of over 1600 cycles with an average Coulombic efficiency of up to 99.6% at 5 mA cm-2. This work provides some conceptions for the evolution and application of high-performance Zn metal batteries.

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