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1.
Cell ; 181(3): 702-715.e20, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32315619

RESUMO

Protein phosphatase 2A (PP2A) enzymes can suppress tumors, but they are often inactivated in human cancers overexpressing inhibitory proteins. Here, we identify a class of small-molecule iHAPs (improved heterocyclic activators of PP2A) that kill leukemia cells by allosterically assembling a specific heterotrimeric PP2A holoenzyme consisting of PPP2R1A (scaffold), PPP2R5E (B56ε, regulatory), and PPP2CA (catalytic) subunits. One compound, iHAP1, activates this complex but does not inhibit dopamine receptor D2, a mediator of neurologic toxicity induced by perphenazine and related neuroleptics. The PP2A complex activated by iHAP1 dephosphorylates the MYBL2 transcription factor on Ser241, causing irreversible arrest of leukemia and other cancer cells in prometaphase. In contrast, SMAPs, a separate class of compounds, activate PP2A holoenzymes containing a different regulatory subunit, do not dephosphorylate MYBL2, and arrest tumor cells in G1 phase. Our findings demonstrate that small molecules can serve as allosteric switches to activate distinct PP2A complexes with unique substrates.


Assuntos
Proteína Fosfatase 2/metabolismo , Apoptose , Proteínas de Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Ativadores de Enzimas/metabolismo , Fase G1 , Humanos , Complexos Multiproteicos/metabolismo , Complexos Multiproteicos/fisiologia , Fenotiazinas/farmacologia , Fosforilação , Proteína Fosfatase 2/fisiologia , Subunidades Proteicas/metabolismo , Transativadores/efeitos dos fármacos , Transativadores/metabolismo , Fatores de Transcrição/metabolismo
3.
Nano Lett ; 24(5): 1717-1728, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38270376

RESUMO

Surgery is the primary method to treat malignant melanoma; however, the residual microtumors that cannot be resected completely often trigger tumor recurrence, causing tumor-related mortality following melanoma resection. Herein, we developed a feasible strategy based on the combinational chemoimmunotherapy by cross-linking carboxymethyl chitosan (CMCS)-originated polymetformin (PolyMetCMCS) with cystamine to prepare stimuli-responsive nanogel (PMNG) owing to the disulfide bond in cystamine that can be cleaved by the massive glutathione (GSH) in tumor sites. Then, chemotherapeutic agent doxorubicin (DOX) was loaded in PMNG, which was followed by a hyaluronic acid coating to improve the overall biocompatibility and targeting ability of the prepared nanogel (D@HPMNG). Notably, PMNG effectively reshaped the tumor immune microenvironment by reprogramming tumor-associated macrophage phenotypes and recruiting intratumoral CD8+ T cells owing to the inherited immunomodulatory capability of metformin. Consequently, D@HPMNG treatment remarkably suppressed melanoma growth and inhibited its recurrence after surgical resection, proposing a promising solution for overcoming lethal melanoma recurrence.


Assuntos
Melanoma , Polietilenoglicóis , Polietilenoimina , Humanos , Nanogéis , Macrófagos Associados a Tumor , Cistamina , Linfócitos T CD8-Positivos , Doxorrubicina , Glutationa/química , Microambiente Tumoral , Linhagem Celular Tumoral
4.
Nano Lett ; 24(22): 6767-6777, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38771956

RESUMO

Efforts to prolong the blood circulation time and bypass immune clearance play vital roles in improving the therapeutic efficacy of nanoparticles (NPs). Herein, a multifunctional nanoplatform (BPP@RTL) that precisely targets tumor cells is fabricated by encapsulating ultrasmall phototherapeutic agent black phosphorus quantum dot (BPQD), chemotherapeutic drug paclitaxel (PTX), and immunomodulator PolyMetformin (PM) in hybrid membrane-camouflaged liposomes. Specifically, the hybrid cell membrane coating derived from the fusion of cancer cell membrane and red blood cell membrane displays excellent tumor targeting efficiency and long blood circulation property due to the innate features of both membranes. After collaboration with aPD-L1-based immune checkpoint blockade therapy, a boosted immunotherapeutic effect is obtained due to elevated dendritic cell maturation and T cell activation. Significantly, laser-irradiated BPP@RTL combined with aPD-L1 effectively eliminates primary tumors and inhibits lung metastasis in 4T1 breast tumor model, offering a promising treatment plan to develop personalized antitumor strategy.


Assuntos
Imunoterapia , Paclitaxel , Fósforo , Pontos Quânticos , Pontos Quânticos/química , Pontos Quânticos/uso terapêutico , Animais , Fósforo/química , Camundongos , Paclitaxel/química , Paclitaxel/uso terapêutico , Paclitaxel/farmacologia , Paclitaxel/administração & dosagem , Feminino , Humanos , Linhagem Celular Tumoral , Lipossomos/química , Nanopartículas/química , Camundongos Endogâmicos BALB C
5.
Invest New Drugs ; 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39369144

RESUMO

Studies have shown that the Zinc finger homeobox 4 (ZFHX4) might be a factor in the prognosis of malignancies. However, little is known about the association between the ZFHX4 mutation and the effectiveness of immune checkpoint inhibitors (ICIs) in non-small cell lung cancer (NSCLC) and melanoma. Three public ICIs-treated NSCLC cohorts were divided into discovery cohort (n=75) and validation cohort (n=62), which were used to evaluate the relationship between ZFHX4 mutation and ICIs effectiveness in NSCLC. Seven ICIs-treated melanoma cohorts (n = 418) were used to analyze the relationship between ZFHX4 mutation and immunotherapy efficacy in melanoma. NSCLC and skin cutaneous melanoma (SKCM) cohorts from The Cancer Genome Atlas (TCGA) were used to investigate underlying mechanism. Patients with ZFHX4 mutant-type (ZFHX4-Mut) showed a superior objective response rate (ORR) (P < 0.01) and longer progression-free survival (PFS) (P < 0.05) than patients with ZFHX4 wild-type (ZFHX4-WT) in NSCLC cohorts. In the melanoma cohorts, patients carrying ZFHX4-Mut had a higher ORR (P = 0.042) and longer overall survival (OS) (P = 0.011). Besides, patients with NSCLC and melanoma harboring ZFHX4-Mut had a higher tumor mutation burden (TMB) (P<0.001) and tumor neoantigen burden (TNB) (P<0.001) than those harboring ZFHX4-WT. ZFHX4 mutation was associated with higher levels of plasma B cells, activated CD4+ memory T cells, and CD8+ T cells. Seven DNA damage repair pathways were significantly enriched in the ZFHX4-Mut group. ZFHX4 mutation could serve as a predicter for the efficacy of ICIs therapy in NSCLC and melanoma.

6.
Reproduction ; 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39312641

RESUMO

Thousands of genes are activated in late 2-cell embryos, which means that numerous pre-mRNAs are generated during this time. These pre-mRNAs must be accurately spliced to ensure that the mature mRNAs are translated to functional proteins. However, little is known about the roles of pre-mRNA splicing and cellular factors modulating pre-mRNA splicing during early embryonic development. Here, we report that downregulation of SON, a large Ser/Arg (SR)-related protein, reduced embryonic development and caused deficient blastomere cleavage. These embryonic developmental defects result from dysregulated nuclear speckle organization and pre-mRNA splicing of a set of cell cycle-related genes. Furthermore, SON downregulation disrupted the transcriptome (2128 upregulated and 1399 downregulated) in 4-cell embryos. Increased H3K4me3, H3K9me3 and H3K27me3 levels were detected in 4-cell embryos after SON downregulation. Taken together, these results demonstrate that accurate pre-mRNA splicing is essential for early embryonic development and that SON plays important roles in nuclear speckle organization, pre-mRNA splicing, transcriptome establishment and histone methylation reprogramming during early embryonic development.

7.
Inorg Chem ; 63(21): 9983-9991, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38757519

RESUMO

Electrocatalytic CO2 reduction reaction (CO2RR) to ethanol has been widely researched for potential commercial application. However, it still faces limited selectivity at a large current density. Herein, Mo4+-doped CuS nanosheet-assembled hollow spheres are constructed to address this issue. Mo4+ ion doping modifies the local electronic environments and diversifies the binding sites of CuS, which increases the coverage of linear *COL and produces bridge *COB for subsequent *COL-*COH coupling toward ethanol production. The optimal Mo9.0%-CuS can electrocatalyze CO2 to ethanol with a faradaic efficiency of 67.5% and a partial current density of 186.5 mA cm-2 at -0.6 V in a flow cell. This work clarifies that doping high valence transition metal ions into Cu-based sulfides can regulate the coverage and configuration of related intermediates for ethanol production during the CO2RR in a flow cell.

8.
J Immunol ; 208(2): 420-428, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34903640

RESUMO

There are urgent needs for humanized mouse models of viral respiratory diseases to study immunopathogenesis and therapeutic interventions. Although human immune system (HIS) mice permit analysis in real time of human immune responses in vivo, evolutionary divergences preclude their usefulness for the respiratory viruses that do not infect mouse lungs. In this study, we sought to use HIS mice with human lung (HL) tissue xenografts (HISL mice) to address this issue. The grafted HL tissue maintained histologically normal structure, and populated with human tissue-resident immune cells, including CD11c+ dendritic cells and CD4+ and CD8+ tissue-resident memory T cells. HISL mice showed a marked expansion of tissue-resident memory T cells and generation of viral Ag-specific T cells in the HL xenografts, and production of antiviral IgM and IgG Abs upon immunization of the HL xenograft by H1N1 influenza viruses. RNA-seq analysis on H1N1-infected and control HL xenografts identified a total of 5089 differentially expressed genes with enrichments for genes involved in respiratory diseases, viral infections, and associated immune responses. Furthermore, prophylactic viral exposures resulted in protection against subsequent lethal challenge by intranasal viral inoculation. This study supports the usefulness of this preclinical model in exploring the immunopathology and therapies of respiratory viral diseases.


Assuntos
Anticorpos Antivirais/sangue , Células Dendríticas/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Células T de Memória/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Animais , Anticorpos Antivirais/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Xenoenxertos , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Memória Imunológica/imunologia , Pulmão/citologia , Pulmão/imunologia , Transplante de Pulmão/métodos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Infecções por Orthomyxoviridae/imunologia , Vacinação
9.
Death Stud ; 48(4): 326-351, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37390123

RESUMO

This study aims to explore circumstances affecting patients' euthanasia and medically assisted suicide (MAS) decisions from the perspectives of patients, relatives, and healthcare professionals. A qualitative systematic review was performed following PRISMA recommendations. The review protocol is registered in PROSPERO (CRD42022303034). Literature searches were conducted in MEDLINE, EMBASE, CINAHL Complete, Eric, PsycInfo, and citation pearl search in Scopus from 2012 to 2022. In total, 6840 publications were initially retrieved. The analysis included a descriptive numerical summary analysis and a qualitative thematic analysis of 27 publications, resulting in two main themes-Contexts and factors influencing actions and interactions, and Finding support while dealing with resistance in euthanasia and MAS decisions-and related sub-themes. The results illuminated the dynamics in (inter)actions between patients and involved parties that might both impede and facilitate patients' decisions related to euthanasia/MAS, potentially influencing patients' decision-making experiences, and the roles and experiences of involved parties.


Assuntos
Eutanásia , Suicídio Assistido , Humanos , Pesquisa Qualitativa , Pessoal de Saúde , Atenção à Saúde
10.
J Youth Adolesc ; 53(10): 2251-2265, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38767792

RESUMO

The daily reciprocal relations between parental psychological aggression and adolescent anxiety and the heterogeneity, i.e., whether these relations vary across different adolescents, remain unclear. This study examined this issue with a 15-day daily diary study among 326 Chinese adolescents (Mage = 14.53 years, SD = 0.60, 47.2% girls). Dynamic structural equation models revealed that parental psychological aggression co-fluctuated with adolescent anxiety within a day. For lagged associations, only father-driven effects were supported but not mother-driven effects, whereas child-driven effects were supported for both parents. These within-person associations were heterogeneous across adolescents. Moreover, adolescents with more parental psychological aggression reported higher anxiety. This study revealed the reciprocal relations between parental psychological aggression and adolescent anxiety at the micro timescale and also highlighted that the within-person associations were heterogeneous across different adolescents.


Assuntos
Agressão , Ansiedade , Relações Pais-Filho , Humanos , Adolescente , Feminino , Masculino , Agressão/psicologia , China , Ansiedade/psicologia , Pais/psicologia , Comportamento do Adolescente/psicologia , Diários como Assunto
11.
Chin J Traumatol ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38762419

RESUMO

PURPOSE: To methodically assess the effectiveness of augmentative plating (AP) and exchange nailing (EN) in managing nonunion following intramedullary nailing for long bone fractures of the lower extremity. METHODS: PubMed, EMBASE, Web of Science, and the Cochrane Library were searched to gather clinical studies regarding the use of AP and EN techniques in the treatment of nonunion following intramedullary nailing of lower extremity long bones. The search was conducted up until May 2023. The original studies underwent an independent assessment of their quality, a process conducted utilizing the Newcastle-Ottawa scale. Data were retrieved from these studies, and meta-analysis was executed utilizing Review Manager 5.3. RESULTS: This meta-analysis included 8 studies involving 661 participants, with 305 in the AP group and 356 in the EN group. The results of the meta-analysis demonstrated that the AP group exhibited a higher rate of union (odds ratio: 8.61, 95% confidence intervals (CI): 4.12 - 17.99, p < 0.001), shorter union time (standardized mean difference (SMD): -1.08, 95 % CI: -1.79 - -0.37, p = 0.003), reduced duration of the surgical procedure (SMD: -0.56, 95 % CI: -0.93 - -0.19, p = 0.003), less bleeding (SMD: -1.5, 95 % CI: -2.81 - -0.18), p = 0.03), and a lower incidence of complications (relative risk: -0.17, 95 % CI: -0.27 - -0.06, p = 0.001). In the subgroup analysis, the time for union in the AP group in nonisthmal and isthmal nonunion of lower extremity long bones was shorter compared to the EN group (nonisthmal SMD: -1.94, 95 % CI: -3.28 - -0.61, p < 0.001; isthmal SMD: -1.08, 95 % CI: -1.64 - -0.52, p = 0.002). CONCLUSION: In the treatment of nonunion in diaphyseal fractures of the long bones in the lower extremity, the AP approach is superior to EN, both intraoperatively (with reduced duration of the surgical procedure and diminished blood loss) and postoperatively (with an elevated union rate, shorter union time, and lower incidence of complications). Specifically, in the management of nonunion of lower extremity long bones with non-isthmal and isthmal intramedullary nails, AP demonstrated shorter union time in comparison to EN.

12.
Chin J Traumatol ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38811319

RESUMO

PURPOSE: We carried out the study aiming to explore and analyze the risk factors, the distribution of pathogenic bacteria, and their antibiotic-resistance characteristics influencing the occurrence of surgical site infection (SSI), to provide valuable assistance for reducing the incidence of SSI after traumatic fracture surgery. METHODS: A retrospective case-control study enrolling 3978 participants from January 2015 to December 2019 receiving surgical treatment for traumatic fractures was conducted at Tangdu Hospital of Air Force Medical University. Baseline data, demographic characteristics, lifestyles, variables related to surgical treatment, and pathogen culture were harvested and analyzed. Univariate analyses and multivariate logistic regression analyses were used to reveal the independent risk factors of SSI. A bacterial distribution histogram and drug-sensitive heat map were drawn to describe the pathogenic characteristics. RESULTS: Included 3978 patients 138 of them developed SSI with an incidence rate of 3.47% postoperatively. By logistic regression analysis, we found that variables such as gender (males) (odds ratio (OR) = 2.012, 95% confidence interval (CI): 1.235 - 3.278, p = 0.005), diabetes mellitus (OR = 5.848, 95% CI: 3.513 - 9.736, p < 0.001), hypoproteinemia (OR = 3.400, 95% CI: 1.280 - 9.031, p = 0.014), underlying disease (OR = 5.398, 95% CI: 2.343 - 12.438, p < 0.001), hormonotherapy (OR = 11.718, 95% CI: 6.269 - 21.903, p < 0.001), open fracture (OR = 29.377, 95% CI: 9.944 - 86.784, p < 0.001), and intraoperative transfusion (OR = 2.664, 95% CI: 1.572 - 4.515, p < 0.001) were independent risk factors for SSI, while, aged over 59 years (OR = 0.132, 95% CI: 0.059 - 0.296, p < 0.001), prophylactic antibiotics use (OR = 0.082, 95% CI: 0.042 - 0.164, p < 0.001) and vacuum sealing drainage use (OR = 0.036, 95% CI: 0.010 - 0.129, p < 0.001) were protective factors. Pathogens results showed that 301 strains of 38 species of bacteria were harvested, among which 178 (59.1%) strains were Gram-positive bacteria, and 123 (40.9%) strains were Gram-negative bacteria. Staphylococcus aureus (108, 60.7%) and Enterobacter cloacae (38, 30.9%) accounted for the largest proportion. The susceptibility of Gram-positive bacteria to Vancomycin and Linezolid was almost 100%. The susceptibility of Gram-negative bacteria to Imipenem, Amikacin, and Meropenem exceeded 73%. CONCLUSION: Orthopedic surgeons need to develop appropriate surgical plans based on the risk factors and protective factors associated with postoperative SSI to reduce its occurrence. Meanwhile, it is recommended to strengthen blood glucose control in the early stage of admission and for surgeons to be cautious and scientific when choosing antibiotic therapy in clinical practice.

13.
Angew Chem Int Ed Engl ; 63(7): e202315325, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38155608

RESUMO

An atom- and step-economical and redox-neutral cascade reaction enabled by asymmetric bimetallic relay catalysis by merging a ruthenium-catalyzed asymmetric borrowing-hydrogen reaction with copper-catalyzed asymmetric Michael addition has been realized. A variety of highly functionalized 2-amino-5-hydroxyvaleric acid esters or peptides bearing 1,4-non-adjacent stereogenic centers have been prepared in high yields with excellent enantio- and diastereoselectivity. Judicious selection and rational modification of the Ru catalysts with careful tuning of the reaction conditions played a pivotal role in stereoselectivity control as well as attenuating undesired α-epimerization, thus enabling a full complement of all four stereoisomers that were otherwise inaccessible in previous work. Concise asymmetric stereodivergent synthesis of the key intermediates for biologically important chiral molecules further showcases the synthetic utility of this methodology.


Assuntos
Cobre , Rutênio , Aminoácidos/química , Catálise , Cobre/química , Peptídeos , Estereoisomerismo
14.
BMC Bioinformatics ; 24(1): 363, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37759189

RESUMO

BACKGROUND: Autism spectrum disorder (ASD) is a serious developmental disorder of the brain. Recently, various deep learning methods based on functional magnetic resonance imaging (fMRI) data have been developed for the classification of ASD. Among them, graph neural networks, which generalize deep neural network models to graph structured data, have shown great advantages. However, in graph neural methods, because the graphs constructed are homogeneous, the phenotype information of the subjects cannot be fully utilized. This affects the improvement of the classification performance. METHODS: To fully utilize the phenotype information, this paper proposes a heterogeneous graph convolutional attention network (HCAN) model to classify ASD. By combining an attention mechanism and a heterogeneous graph convolutional network, important aggregated features can be extracted in the HCAN. The model consists of a multilayer HCAN feature extractor and a multilayer perceptron (MLP) classifier. First, a heterogeneous population graph was constructed based on the fMRI and phenotypic data. Then, a multilayer HCAN is used to mine graph-based features from the heterogeneous graph. Finally, the extracted features are fed into an MLP for the final classification. RESULTS: The proposed method is assessed on the autism brain imaging data exchange (ABIDE) repository. In total, 871 subjects in the ABIDE I dataset are used for the classification task. The best classification accuracy of 82.9% is achieved. Compared to the other methods using exactly the same subjects in the literature, the proposed method achieves superior performance to the best reported result. CONCLUSIONS: The proposed method can effectively integrate heterogeneous graph convolutional networks with a semantic attention mechanism so that the phenotype features of the subjects can be fully utilized. Moreover, it shows great potential in the diagnosis of brain functional disorders with fMRI data.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Redes Neurais de Computação , Fenótipo
15.
Eur J Immunol ; 52(10): 1640-1647, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35976660

RESUMO

There is an urgent need for animal models of coronavirus disease 2019 to study immunopathogenesis and test therapeutic intervenes. In this study, we showed that NOD/SCID IL2rg-/- (NSG) mice engrafted with human lung (HL) tissue (NSG-L mice) could be infected efficiently by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and that live virus capable of infecting Vero cells was found in the HL grafts and multiple organs from infected NSG-L mice. RNA-Sequencing identified a series of differentially expressed genes, which are enriched in viral defense responses, chemotaxis, IFN stimulation and pulmonary fibrosis, between HL grafts from infected and control NSG-L mice. Furthermore, when infected with SARS-CoV-2, humanized mice with both human immune system (HIS) and autologous HL grafts (HISL mice) had bodyweight loss and hemorrhage and immune cell infiltration in HL grafts, which were not observed in immunodeficient NSG-L mice, indicating the development of anti-viral immune responses in these mice. In support of this possibility, the infected HISL mice showed bodyweight recovery and lack of detectable live virus at the later time. These results demonstrate that NSG-L and HISL mice are susceptible to SARS-CoV-2 infection, offering a useful in vivo model for studying SARS-CoV-2 infection and the associated immune response and immunopathology, and testing anti-SARS-CoV-2 therapies.


Assuntos
COVID-19 , Animais , Chlorocebus aethiops , Modelos Animais de Doenças , Humanos , Imunidade , Pulmão , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , RNA , SARS-CoV-2 , Células Vero
16.
Microb Cell Fact ; 22(1): 56, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36964553

RESUMO

BACKGROUND: L­Fucose is a rare sugar that has beneficial biological activities, and its industrial production is mainly achieved with brown algae through acidic/enzymatic fucoidan hydrolysis and a cumbersome purification process. Fucoidan is synthesized through the condensation of a key substance, guanosine 5'­diphosphate (GDP)­L­fucose. Therefore, a more direct approach for biomanufacturing L­fucose could be the enzymatic degradation of GDP­L­fucose. However, no native enzyme is known to efficiently catalyze this reaction. Therefore, it would be a feasible solution to engineering an enzyme with similar function to hydrolyze GDP­L­fucose. RESULTS: Herein, we constructed a de novo L­fucose synthetic route in Bacillus subtilis by introducing heterologous GDP­L­fucose synthesis pathway and engineering GDP­mannose mannosyl hydrolase (WcaH). WcaH displays a high binding affinity but low catalytic activity for GDP­L­fucose, therefore, a substrate simulation­based structural analysis of the catalytic center was employed for the rational design and mutagenesis of selected positions on WcaH to enhance its GDP­L­fucose­splitting efficiency. Enzyme mutants were evaluated in vivo by inserting them into an artificial metabolic pathway that enabled B. subtilis to yield L­fucose. WcaHR36Y/N38R was found to produce 1.6 g/L L­fucose during shake­flask growth, which was 67.3% higher than that achieved by wild­type WcaH. The accumulated L­fucose concentration in a 5 L bioreactor reached 6.4 g/L. CONCLUSIONS: In this study, we established a novel microbial engineering platform for the fermentation production of L­fucose. Additionally, we found an efficient GDP­mannose mannosyl hydrolase mutant for L­fucose biosynthesis that directly hydrolyzes GDP­L­fucose. The engineered strain system established in this study is expected to provide new solutions for L­fucose or its high value­added derivatives production.


Assuntos
Hidrolases , Manose , Hidrolases/metabolismo , Manose/metabolismo , Fucose/metabolismo , Bacillus subtilis/genética , Reatores Biológicos , Fermentação , Engenharia Metabólica
17.
Lasers Med Sci ; 39(1): 16, 2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38141129

RESUMO

Pulsed dye laser (PDL) is the most commonly used method for port-wine stain (PWS); however, no studies have reported the safety of PDL. This review aimed to collect and summarize complications reported in relevant literature, assess complication rates in treating PWS with PDL, and explore the relevant influencing factors. A systematic review and meta-analysis were conducted to search for related studies in PubMed, Embase, and the Cochrane Library until August 2022. Two reviewers independently evaluated the risk of bias of included studies. Stata Software version 17.0 was used for the analysis. All complications reported in the literature are divided into acute phase complications and long-term complications. Overall pooled purpura, edema, crusting, blistering, hyperpigmentation, hypopigmentation, and scarring rates were 98.3%, 97.6%, 21.5%, 8.7%, 12.8%, 0.9%, and 0.2%, respectively. Although the acute adverse reactions were found to be common, the long-term permanent complications clearly have a lower frequency, and the occurrence of scarring is much lower than that initially thought. This indicates that effective protective measures after treatment are very important for preventing scar formation. Overall, PDL treatment for PWS shows a high level of safety and low chances of causing long-term complications.


Assuntos
Lasers de Corante , Mancha Vinho do Porto , Humanos , Mancha Vinho do Porto/radioterapia , Mancha Vinho do Porto/cirurgia , Resultado do Tratamento , Lasers de Corante/efeitos adversos , Cicatriz , Terapia Combinada
18.
Chem Biodivers ; 20(1): e202200393, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36471653

RESUMO

Potamogeton crispus L. (P. crispus) is the type of a widely distributed perennial herbs, which is rich in rhodoxanthin. In this research work, five antioxidant indexes in vitro were selected to study the antioxidant activity of rhodoxanthin from P. crispus (RPC). A model of hydrogen peroxide (H2 O2 ) -induced oxidative damage in RAW264.7 cells was established to analyze the antioxidant effect and potential mechanism of RPC. The levels of ROS, MDA and the activities of oxidation related enzymes by H2 O2 were determined by enzyme linked immunosorbent assay (ELISA). The mRNA expression of Nrf-2, HO-1, SOD1 and SOD2 was measured by qRT-PCR assay. According to the results, RPC had free radical scavenging ability for 2, 2-diphenyl-1-trinitrohydrazine (DPPH), 2,2'-azinobis(3-ethylbenzo-thiazoline-6-sulfonic acid radical ion) (ABTS), hydroxyl radical and superoxide anion. RPC significantly decreased the level of MDA and ROS and LDH activity, while increased GSH level and activities of SOD, GSH-Px and CAT. It was showed that RPC could increase the mRNA expression of Nrf-2, HO-1, SOD1 and SOD2 in RAW264.7 cells in a dose-dependently manner. In summary, RPC treatment could effectively attenuate the H2 O2 -induced cell damage rate, and the mechanism is related to the reduction of H2 O2 induced oxidative stress and the activation of Nrf-2 pathway.


Assuntos
Antioxidantes , Potamogetonaceae , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Potamogetonaceae/genética , Potamogetonaceae/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase-1/metabolismo , Superóxido Dismutase-1/farmacologia , Estresse Oxidativo , Macrófagos , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/metabolismo , RNA Mensageiro/metabolismo
19.
J Microencapsul ; 40(8): 649-662, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37867421

RESUMO

To improve the stability of fucoxanthin, fucoxanthin liposomes (L) were prepared by the thin-film ultrasound method, and fucoxanthin liposomes were modified with sodium alginate and chitosan by an electrostatic deposition method. The release characteristics of fucoxanthin in different types of liposomes with in vitro gastrointestinal simulation were studied. Under the optimum conditions, the results showed that the encapsulation efficiency of prepared liposomes could reach 88.56 ± 1.40% (m/m), with an average particle size of 295.27 ± 7.28 nm, a Zeta potential of -21.53 ± 2.00 mV, a polydispersity index (PDI) of 0.323 ± 0.007 and a loading capacity of 33.3 ± 0.03% (m/m). Compared with L and chitosan modified fucoxanthin liposomes (CH), sodium alginate and chitosan modified fucoxanthin liposomes (SA-CH) exhibited higher storage stability, in vitro bioaccessibility and antioxidant activity after gastrointestinal digestion. Sodium alginate and chitosan co-modified liposomes can be developed as formulations for encapsulation and delivery of functional ingredients, providing a theoretical basis for developing new fucoxanthin series products.


Assuntos
Quitosana , Lipossomos , Sistemas de Liberação de Medicamentos/métodos , Antioxidantes , Alginatos , Tamanho da Partícula
20.
Nurs Crit Care ; 28(5): 645-652, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37186353

RESUMO

BACKGROUND: Delirium is one of the most common complications in critically ill children. Once delirium occurs, it will cause physical and psychological distress in children and increase the length of their ICU stay and hospitalization costs. Understanding the risk factors for delirium in critically ill children can help develop targeted nursing interventions to reduce the incidence of delirium. AIMS: To investigate the incidence and the risk factors of delirium in the paediatric intensive care unit (PICU). STUDY DESIGN: We performed a prospective observational study in critically ill patients in the PICU between February and July 2020. Delirium was diagnosed by the Cornell Assessment of Paediatric Delirium (CAPD) and the Richmond Agitation Sedation Scale and analysed via univariate analysis and multivariate logistic regression to determine the independent risk factors of delirium in critically ill children. RESULTS: The study enrolled 315 patients ranging in age from 1-202 (65.3-54.3) months, with 56.2% (n = 177) being male. The incidence of delirium was 29.2% (n = 92) according to CAPD criteria. Among them, 33 cases (35.9%) were of hyperactive delirium, 16 cases (17.4%) were of hypoactive delirium, and 43 cases (46.7%) were of mixed delirium. By using stepwise logistic regression, the independent risk factors of delirium included mechanical ventilation (odds ratio [OR], 11.470; 95% confidence interval [CI], 4.283-30.721), nervous system disease (OR, 5.596; 95%CI, 2.445 to 12.809), developmental delay (OR, 5.157; 95% CI, 1.990-13.363), benzodiazepine (OR, 3.359; 95% CI 1.278-8.832), number of catheters (OR, 1.918; 95% CI, 1.425 to 2.582), and age (OR, 0.985; 95% confidence interval CI, 0.976-0.993). CONCLUSIONS: Delirium is a common complication in the PICU. The independent risk factors include mechanical ventilation, nervous system disease, developmental delay, benzodiazepines, higher number of catheters, and younger age. This study may help develop intervention strategies to reduce the incidence of delirium in critically ill children by targeting modifiable risk factors. RELEVANCE TO CLINICAL PRACTICE: Recommendations for practice include paying attention to high-risk children in the ICU who are prone to delirium, removing influencing factors as soon as possible, and providing targeted nursing interventions.


Assuntos
Estado Terminal , Delírio , Humanos , Masculino , Criança , Feminino , Delírio/epidemiologia , Delírio/etiologia , Delírio/diagnóstico , Unidades de Terapia Intensiva Pediátrica , Estudos Prospectivos , Fatores de Risco , Unidades de Terapia Intensiva
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