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1.
Int J Biol Macromol ; 267(Pt 2): 131285, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38583841

RESUMO

Thermal stability and iron saturation of lactoferrin (LF) are of great significance not only for the evaluation of the biological activities of LF but also for the optimization of the isolation and drying process parameters. Differential scanning calorimetry (DSC) is a well-established and efficient method for thermal stability and iron saturation detection in LF. However, multiple DSC measurements are typically performed sequentially, thus time-consuming and low throughput. Herein, we introduced the differential scanning fluorimetry (DSF) approach to overcome such limitations. The DSF can monitor LF thermal unfolding with a commonly available real-time PCR instrument and a fluorescent dye (SYPRO orange or Glomelt), and the measured melting temperature of LF is consistent with that determined by DSC. On the basis of that, a new quantification method was established for determination of iron saturation levels using the linear correlation of the degree of ion saturation of LF with DSF measurements. Such DSF method is simple, inexpensive, rapid (<15 min), and high throughput (>96 samples per experiment), and provides a valuable alternative tool for thermal stability detection of LF and other whey proteins.


Assuntos
Fluorometria , Ferro , Lactoferrina , Estabilidade Proteica , Lactoferrina/química , Lactoferrina/análise , Ferro/química , Fluorometria/métodos , Varredura Diferencial de Calorimetria/métodos , Temperatura , Ensaios de Triagem em Larga Escala/métodos
2.
Chem Biodivers ; : e202400140, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568379

RESUMO

OBJECTIVES: Dandelion has been shown to exert anti-inflammatory and anti-bacterial effects. Our study aimed to identify the effect and mechanism of dandelion flower extracts on H. pylori-induced gastritis and screen for novel antimicrobial substances. METHODS: Anti-H. pylori activities of water extracts(WEDF) and ethanol extracts (EEDF) of dandelion flowers were performed with disk diffusion method assay, MIC, and MBC. The H. pylori-induced model was constructed to examine the gastroprotective of EEDF using RUT, pathological analysis, and ELISA. RESULTS: EEDF exhibited better anti- H. pylori and urease inhibition activities than WEDF. In vivo studies, EEDF can reduce the adhesion of H. pylori to the gastric mucosa, alleviate gastric damage, and concurrently reduce the levels of TNF-α and IL-6 in gastric tissues. The six phenolic compounds showed urease inhibition effect (IC50: 2.99±0.15 to 66.08±6.46 mmol/mL). Among them, chlorogenic acid, caffeic acid, and luteolin also had anti-H. pylori activity (MIC: 64-256 µg/mL). CONCLUSION: EEDF exhibited anti-H. pylori, gastroprotective and anti-inflammatory effects. Chicoric acid and luteolin may be the main active compounds of dandelion flowers to exert anti-H. pylori, and worthy of further investigation.

3.
ACS Appl Mater Interfaces ; 16(12): 14680-14693, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38497589

RESUMO

Carbon-encapsulated metal (CEM) catalysts effectively address supported metal catalyst instability by protecting the active metal with a shell. However, mass transfer limitations lead to reduced activity for catalytic hydrogenation reaction over most CEM catalysts. Herein, we introduce a dopant strategy aimed at incorporating nickel metal within graphene-like shells (GLS) featuring oxygen-containing functional groups (OFGs). The core of this strategy involves precise control of GLS modification and the demonstrated pivotal influence of aromatic ether linkages (═C-O-C) in GLS for significant enhancement of catalytic performance. The introduction of ═C-O-C into GLS with stability was beneficial to improve the work function of the catalyst and promoted electron transmission from Ni metal core to GLS, further elevating the catalytic activity, based on the Mott-Schottky effect. In addition, the experimental characterization and density functional theory (DFT) calculations showcased that the ═C-O-C reconstructed the electronic state of GLS, imparting it highly specific for the adsorption of hydrogen and para-chloronitrobenzene (p-CNB) to obtain para-chloroaniline (p-CAN) with high selectivity. This work manifested a feasible direction for the precise modulation and design of the OFGs in CEM catalysts to achieve highly efficient catalytic hydrogenation.

4.
Int J Biol Macromol ; 265(Pt 1): 130797, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479662

RESUMO

In recent years, photocatalytic technology has been introduced to develop a new kind antimicrobial agents fighting antibiotic abusing and related drug resistance. The efforts have focused on non-precious metal photocatalysts along with green additives. In the present work, a novel bis-S heterojunctions based on the coupling of polysaccharide (CS) and bismuth-based MOF (CAU-17) s synthesized through a two-step method involving amidation reaction under mild conditions. The as prepared photocatalyst literally extended the light response to the near-infrared region. Owing to its double S-type heterostructure, the lifetime of the photocarriers is significantly prolonged and the redox capacity are enhanced. As a result, the as prepared photocatalyst indicated inhibition up to 99.9 % under 20 min of light exposure against Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria as well as drug-resistant bacteria (MRSA). The outstanding photocatalytic performance is attributed to the effective charge separation and migration due to the unique double S heterostructure. Such a double S heterostructure was confirmed through transient photocurrent response, electrochemical impedance spectroscopy tests and electron spin resonance measurements. The present work provides a basis for the simple synthesis of high-performance heterojunction photocatalytic inhibitors, which extends the application of CAU-17 in environmental disinfection and wastewater purification.


Assuntos
Quitosana , Estruturas Metalorgânicas , Bismuto/química , Escherichia coli , Quitosana/farmacologia , Estruturas Metalorgânicas/farmacologia , Staphylococcus aureus , Catálise
5.
J Agric Food Chem ; 72(13): 7308-7317, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38529564

RESUMO

Kauralexin A1 (KA1) is a key intermediate of the kauralexin A series metabolites of maize phytoalexins. However, their application is severely limited by their low abundance in maize. In this study, an efficient biosynthetic pathway was constructed to produce KA1 in Saccharomyces cerevisiae. Also, metabolic and enzyme engineering strategies were applied to construct the high-titer strains, such as chassis modification, screening synthases, the colocalization of enzymes, and multiple genomic integrations. First, the KA1 precursor ent-kaurene was synthesized using the efficient diterpene synthase GfCPS/KS from Fusarium fujikuroi, and optimized to reach 244.36 mg/L in shake flasks, which displayed a 200-fold increase compared to the initial strain. Then, the KA1 was produced under the catalysis of ZmCYP71Z18 from Zea mays and SmCPR1 from Salvia miltiorrhiza, and the titer was further improved by integrating the fusion protein into the genome. Finally, an ent-kaurene titer of 763.23 mg/L and a KA1 titer of 42.22 mg/L were achieved through a single-stage fed-batch fermentation in a 5 L bioreactor. This is the first report of the heterologous biosynthesis of maize diterpene phytoalexins in S. cerevisiae, which lays a foundation for further pathway reconstruction and biosynthesis of the kauralexin A series maize phytoalexins.


Assuntos
Diterpenos do Tipo Caurano , Diterpenos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fitoalexinas , Diterpenos do Tipo Caurano/metabolismo , Diterpenos/metabolismo , Fermentação , Engenharia Metabólica
6.
J Gastrointest Surg ; 28(3): 259-266, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38445918

RESUMO

BACKGROUND: Diversion colitis (DC) is a prevalent complication of colostomy characterized by intestinal inflammation. This study aimed to investigate the therapeutic potential of somatostatin (SST) in managing DC. METHODS: After establishing a rat DC model, SST was administered via Mini Osmotic Pumps 2001W at a pumping rate of 1.0 µL/h. Various techniques, including hematoxylin and eosin staining, periodic acid-Schiff staining, immunofluorescence staining, and electron microscopy were employed to assess the effects of SST. Intestinal barrier functions were evaluated using Evans blue, enzyme-linked immunosorbent assay, and MacConkey agar. RESULTS: After SST treatment, the significant weight loss and associated high mortality in the DC group were successfully mitigated. Upregulation of claudin-3 and claudin-4 restored mechanical barriers in colon epithelial tissue, whereas protection of goblet cells and stimulation of mucus secretion enhanced mucus barriers. SST effectively reduced leaky gut and alleviated systemic inflammation. CONCLUSION: This study provides initial evidence supporting the efficacy of SST in the treatment of DC. It offers insights into the role of SST in DC by elucidating its ability to restore damaged intestinal barriers.


Assuntos
Colite , Colostomia , Animais , Ratos , Colostomia/efeitos adversos , Rios , Colite/tratamento farmacológico , Colite/cirurgia , Somatostatina/uso terapêutico , Inflamação
7.
Small ; 20(5): e2304047, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37752779

RESUMO

Microbial infections based on drug-resistant pathogenic organisms following surgery or trauma and uncontrolled bleeding are the main causes of increased mortality from trauma worldwide. The prevalence of drug-resistant pathogens has led to a significant increase in medical costs and poses a great threat to the normal life of people. This is an important issue in the field of biomedicine, and the emergence of new antimicrobial materials hydrogels holds great promise for solving this problem. Hydrogel is an important material with good biocompatibility, water absorption, oxygen permeability, adhesion, degradation, self-healing, corrosion resistance, and controlled release of drugs as well as structural diversity. Bacteria-disturbing hydrogels have important applications in the direction of surgical treatment, wound dressing, medical device coating, and tissue engineering. This paper reviews the classification of antimicrobial hydrogels, the current status of research, and the potential of antimicrobial hydrogels for one application in biomedicine, and analyzes the current research of hydrogels in biomedical applications from five aspects: metal-loaded hydrogels, drug-loaded hydrogels, carbon-material-loaded hydrogels, hydrogels with fixed antimicrobial activity and biological antimicrobial hydrogels, and provides an outlook on the high antimicrobial activity, biodegradability, biocompatibility, injectability, clinical applicability and future development prospects of hydrogels in this field.


Assuntos
Anti-Infecciosos , Hidrogéis , Humanos , Hidrogéis/química , Anti-Infecciosos/farmacologia , Bactérias , Bandagens , Antibacterianos/química
8.
Environ Geochem Health ; 46(1): 12, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38147164

RESUMO

To conduct a precise health risk assessment of heavy metals (HMs) in soil, it is imperative to ascertain the primary sources of potential health risks. In this study, we conducted comprehensive measurements of HMs, specifically focusing on the accumulation of Cu, Cd, Sb, Zn, and Pb in local soil, which may pose threats to environmental quality. To achieve our objective, we employed a method that combines positive matrix factorization with a health risk assessment model to quantify the health risks associated with specific sources. The results obtained from the geo-accumulation index indicate that the majority of HMs found in the local soil are influenced by anthropogenic activities. Among these sources, local industrial-related activities contributed the largest proportion of HMs to the soil at 34.7%, followed by natural sources at 28.7%, mining and metallurgy-related activities at 28.2%, and traffic-related activities at 8.40%. Although the non-carcinogenic and carcinogenic risks associated with individual HMs were found to be below safety thresholds, the cumulative health risks stemming from total HMs exceeded safety limits for children. Moreover, the unacceptable health risks for children originating from industrial-related activities, natural sources, and mining and metallurgy-related activities were primarily concentrated in proximity to mining sites and industrial areas within the local region. This investigation furnishes valuable insights that can aid governmental authorities in formulating precise control policies to mitigate health threats posed by soils in polymetallic mining areas.


Assuntos
Metalurgia , Metais Pesados , Criança , Humanos , China , Metais Pesados/toxicidade , Medição de Risco , Solo
9.
Nutrients ; 15(22)2023 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-38004229

RESUMO

Objectives: Vitamin D (VitD) and Vitamin D receptor (VDR) are suggested to play protective roles in the intestinal barrier in ulcerative colitis (UC). However, the underlying mechanisms remain elusive. Evidence demonstrates that Na+/H+ exchanger isoform 8 (NHE8, SLC9A8) is essential in maintaining intestinal homeostasis, regarded as a promising target for UC therapy. Thus, this study aims to investigate the effects of VitD/VDR on NHE8 in intestinal protection. Methods: VitD-deficient mice, VDR-/- mice and NHE8-/- mice were employed in this study. Colitis mice were established by supplementing DSS-containing water. Caco-2 cells and 3D-enteroids were used for in vitro studies. VDR siRNA (siVDR), VDR over-expression plasmid (pVDR), TNF-α and NF-κb p65 inhibitor QNZ were used for mechanical studies. The expression of interested proteins was detected by multiple techniques. Results: In colitis mice, paricalcitol upregulated NHE8 expression was accompanied by restoring colonic mucosal injury. In VitD-deficient and VDR-/- colitis mice, NHE8 expression was compromised with more serious mucosal damage. Noteworthily, paricalcitol could not prevent intestinal barrier dysfunction and histological destruction in NHE8-/- mice. In Caco-2 cells and enteroids, siVDR downregulated NHE8 expression, further promoted TNF-α-induced NHE8 downregulation and stimulated TNF-α-induced NF-κb p65 phosphorylation. Conversely, QNZ blocked TNF-α-induced NHE8 downregulation in the absence or presence of siVDR. Conclusions: Our study indicates depressed NHE8 expression is responsible for VitD-deficient-induced colitis aggravation. These findings provide novel insights into the molecular mechanisms of VitD/VDR in intestine protection in UC.


Assuntos
Colite Ulcerativa , Colite , Deficiência de Vitamina D , Humanos , Animais , Camundongos , Células CACO-2 , Fator de Necrose Tumoral alfa/metabolismo , NF-kappa B/metabolismo , Colite/metabolismo , Mucosa Intestinal/metabolismo , Vitamina D/metabolismo , Deficiência de Vitamina D/metabolismo , Camundongos Endogâmicos C57BL , Sulfato de Dextrana/efeitos adversos , Colite Ulcerativa/metabolismo
10.
J Transl Med ; 21(1): 696, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37798736

RESUMO

BACKGROUND: Breast cancer is, despite screening, not always detected early enough and is together with other tumor types known to shed genetic information in circulation. Unlike single-copy nuclear DNA, mitochondrial DNA (mtDNA) copies range from 100s to 10,000s per cell, thus providing a potentially alternative to identify potential missing cancer information in circulation at an early stage. METHODS: To characterize mitochondrial mutation landscapes in breast cancer, whole mtDNA sequencing and bioinformatics analyses were performed on 86 breast cancer biopsies and 50 available matched baseline cancer-free whole blood samples from the same individuals, selected from a cohort of middle-aged women in Sweden. To determine whether the mutations can be detected in blood plasma prior to cancer diagnosis, we further designed a nested case-control study (n = 663) and validated the shortlisted mutations using droplet digital PCR. RESULTS: We detected different mutation landscapes between biopsies and matched whole blood samples. Compared to whole blood samples, mtDNA from biopsies had higher heteroplasmic mutations in the D-loop region (P = 0.02), RNR2 (P = 0.005), COX1 (P = 0.037) and CYTB (P = 0.006). Furthermore, the germline mtDNA mutations had higher heteroplasmy level than the lost (P = 0.002) and de novo mutations (P = 0.04). The nonsynonymous to synonymous substitution ratio (dN/dS) was higher for the heteroplasmic mutations (P = 7.25 × 10-12) than that for the homoplasmic mutations, but the de novo (P = 0.06) and lost mutations (P = 0.03) had lower dN/dS than the germline mutations. Interestingly, we found that the critical regions for mitochondrial transcription: MT-HSP1 (odds ratio [OR]: 21.41), MT-TFH (OR: 7.70) and MT-TAS2 (OR: 3.62), had significantly higher heteroplasmic mutations than the rest of the D-loop sub-regions. Finally, we found that the presence of mt.16093T > C mutation increases 67% risk of developing breast cancer. CONCLUSIONS: Our findings show that mitochondrial genetic landscape changes during cancer pathogenesis and positive selection of mtDNA heteroplasmic mutations in breast cancer. Most importantly, the mitochondrial mutations identified in biopsies can be traced back in matched plasma samples and could potentially be used as early breast cancer diagnostic biomarkers.


Assuntos
Neoplasias da Mama , Pessoa de Meia-Idade , Humanos , Feminino , Neoplasias da Mama/genética , Estudos de Casos e Controles , Mutação/genética , DNA Mitocondrial/genética , Mutação em Linhagem Germinativa
11.
J Org Chem ; 88(18): 12935-12948, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37673796

RESUMO

An electrochemical or photoelectrochemical regioselective polyfluoroalkylation/cyclization cascade of 3-aza-1,5-dienes with sodium fluoroalkanesulfinates is presented. This protocol proceeds with a broad substrate scope and good functional group tolerance under mild, oxidant-free, transition-metal-free, and electrolyte-free conditions to provide 3-polyfluoroalkylated 4-pyrrolin-2-ones in one step from readily available N-vinylacrylamides, and it is readily scalable to the Gram scale.

12.
Diabetol Metab Syndr ; 15(1): 158, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37461057

RESUMO

BACKGROUND: Cognitive behavior therapy (CBT) has been applied in intervention research in diabetes patients with satisfying results. However, there was no research on type 2 diabetes (T2DM) patients with comorbidities. This study aimed to investigate the effectiveness of CBT on psychological variables, behavior variables, quality of life, sleep quality, and physical variables among adult T2DM patients with comorbid metabolic syndrome (MS). METHODS: 281 patients aged 18-75 years were recruited from Ningbo First Hospital in China from October 2021 to March 2022. Patients were randomized to the intervention group (IG, N = 148) or control group (CG, N = 133). Patients in the IG received 12 CBT-based sessions during a six-month intervention time. Patients in the CG received the usual care only. Univariate General Linear Model was used to analyze the effect of CBT-based interventions. The analysis was conducted by SPSS Version 28. RESULTS: Results indicated that CBT-based intervention was superior in the following aspects: relieving depression symptoms: IG (4.11 ± 4.35 vs. 1.99 ± 2.12), CG (3.40 ± 3.26 vs. 2.32 ± 1.88), interaction effect (F = 4.074, P = 0.044); enhancing diabetes self-care behaviors: IG (26.79 ± 12.18 vs. 37.49 ± 10.83), CG (25.82 ± 13.71 vs. 31.96 ± 11.72), interaction effect (F = 5.242, P = 0.022); promoting the efficacy of CBT: IG (47.45 ± 6.83 vs. 50.76 ± 4.98), CG (46.74 ± 6.94 vs. 47.87 ± 5.11), interaction effect (F = 5.198, P = 0.023); improving subjective sleep quality: IG (0.93 ± 0.68 vs. 0.69 ± 0.63), CG (1.03 ± 0.72 vs. 1.01 ± 0.68), interaction effect (F = 3.927, P = 0.048). CONCLUSIONS: The CBT-based intervention was beneficial in improving depression symptoms, diabetes self-care behaviors, the efficacy of CBT, and sleep quality in T2DM patients with comorbid MS. The downtrend of body mass index, systolic blood pressure, diastolic pressure, and glycated hemoglobin was larger in the intervention group but not to a significant level. TRIAL REGISTRATION: This study has been prospectively registered at Australia New Zealand Clinical Trials Registry (Registration ID: ACTRN12621001348842 website: https://www.anzctr.org.au/trial/MyTrial.aspx ).

13.
J Am Heart Assoc ; 12(8): e029248, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37026541

RESUMO

Background Abdominal aortic aneurysm (AAA) is a vascular disease with a mortality rate of >80% if ruptured. Mitochondrial dysfunction has been previously implicated in AAA pathogenesis. In this study, we aimed to characterize the mitochondrial genetic landscape in AAA. Methods and Results Whole mitochondrial genome sequencing and bioinformatics analysis were performed in comorbidity matched 48 cases without AAA and 48 cases with AAA, objectively diagnosed, and selected from a cohort of 65-year-old men recruited for a screening program. We identified differential mutational landscapes in men with and without AAA, with errors in mitochondrial DNA replication or repair as potential sources. Heteroplasmic insertions and overall heteroplasmy of structural rearrangements were significantly elevated in AAA cases. Three heteroplasmic variants were associated with risk factors of AAA: leukocyte concentration, plasma glucose, and cholesterol levels, respectively. Interestingly, mutations were more prevalent in regulatory part of the mitochondria, the displacement loop region, in AAA as compared with controls (P value <0.05), especially in the conserved and critical mitochondrial extended termination-associated sequence region. Moreover, we report a novel 24 bp mitochondrial DNA duplication present exclusively in cases with AAA (4%) and 75% of the unmatched AAA biopsies. Finally, the haplogroup cluster JTU was overrepresented in AAA and significantly associated with a positive family history of AAA (odds ratio, 2.9 [95% CI, 1.1-8.1]). Conclusions This is the first study investigating the mitochondrial genome in AAA, where important genetic alterations and haplogroups associated with AAA and clinical risk factors were identified. Our findings have the potential to fill in gaps in the missing genetic information on AAA.


Assuntos
Aneurisma da Aorta Abdominal , Masculino , Humanos , Idoso , Aneurisma da Aorta Abdominal/epidemiologia , Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/diagnóstico , Fatores de Risco , Razão de Chances , Comorbidade , DNA Mitocondrial/genética
14.
Pediatr Neonatol ; 64(5): 562-569, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37105821

RESUMO

BACKGROUND: Birth asphyxia causes hypoxia or inadequate perfusion to the organs of newborns, leading to metabolism dysfunctions including blood glucose disorders. METHODS: Neonates with and without birth asphyxia were retrospectively recruited from 53 hospitals in Hubei Province from January 1 to December 31, 2018. In summary, 875, 1139, and 180 cases in the control group, the mild asphyxia group, and the severe asphyxia group were recruited, respectively. Neonatal blood glucose values at postnatal 1, 2, 6, and 12 h (time error within 0.5 h was allowed) were gathered from the medical records. RESULTS: The incidence rates of hyperglycemia in the control group, the mild asphyxia group and the severe asphyxia group were 2.97%, 7.90%, and 23.33%, respectively (p < 0.001). Additionally, the incidence rates of hypoglycemia in the three groups above were 3.66%, 4.13%, and 7.78%, respectively (p = 0.042). The blood glucose values of neonates with hypoglycemia in the asphyxia group were lower than in the control group (p = 0.003). Furthermore, the blood glucose values of neonates with hyperglycemia were highest in the severe asphyxia group (p < 0.001). There were 778 and 117 cases with blood glucose records at four predefined time points in the mild and severe asphyxia group, respectively. The incidence of blood glucose disorders in the mild asphyxia group significantly decreased from postnatal 6 h (p<0.05). However, we found no obvious changes of the incidence of glucose disorders within postnatal 12 h in the severe asphyxia group (p = 0.589). CONCLUSION: Birth asphyxia is likely to cause neonatal blood glucose disorders, both hypoglycemia and hyperglycemia, during the early postnatal life. The neonates with severe asphyxia have higher incidence, worse severity and longer duration of blood glucose disorders than neonates with mild asphyxia.


Assuntos
Asfixia Neonatal , Hiperglicemia , Hipoglicemia , Doenças do Recém-Nascido , Humanos , Recém-Nascido , Glicemia , Asfixia , Estudos Retrospectivos , Asfixia Neonatal/epidemiologia , Doenças do Recém-Nascido/epidemiologia , Hipoglicemia/epidemiologia , Hipoglicemia/etiologia , Hiperglicemia/epidemiologia , China/epidemiologia
15.
BMC Med Educ ; 23(1): 266, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081445

RESUMO

BACKGROUND: Due to the global outbreak of the COVID-19 epidemic, schools were forced to shift teaching from face-face to online. During this period, a large number of studies on how to better carry out online teaching emerged. However, these studies were basically conducted with domestic students as teaching objects. The research on transnational online education conducted by overseas students is very limited. METHODS: We first conducted a questionnaire survey on the obstacles of transnational online learning of 64 international students from our school who were staying abroad at the beginning of the fall semester of 2020, analyzed the results using the two-tailed student's t-test and changed the teaching platform accordingly and compared the results of the biochemistry exams conducted for 2018 spring class with those of 2018 fall class and the 2019 fall class, so as to verify the superiority of the DingTalk as a transnational online education platform. RESULTS: The results showed that the main difficulties of overseas students in transnational online learning are poor network conditions and time difference. By using DingTalk as an online teaching platform, these difficulties were overcome. In the spring class of 2018, the results of online study students' biochemistry were significantly lower than those of students in face-face study (t-test, p = 0.01). However, after the switch to the DingTalk platform, online students' results in the 2018 fall class (t-test, p = 0.35) and the 2019 fall class (t-test, p = 0.7) were equivalent to the academic performance of face-face students. CONCLUSION: Our exploration and application of DingTalk software in transnational online education successfully solved the dilemma of overseas students' online learning, and provided a feasible method to guarantee the efficacy of online teaching.


Assuntos
COVID-19 , Educação a Distância , Humanos , Universidades , COVID-19/epidemiologia , Pandemias , Instituições Acadêmicas
16.
J Agric Food Chem ; 71(13): 5293-5301, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36967580

RESUMO

Glycine-rich flexible peptide linkers have been widely adopted in fusion protein engineering; however, they can hardly be cleaved for the separation of fusion partners unless specific protease recognition sites are introduced. Herein, we report the use of the peptidoglycan-targeting staphylolytic enzyme lysostaphin to directly digest the glycine-rich flexible linkers of various lengths including oligoglycine linkers and (G4S)x linkers, without the incorporation of extra amino acids. Using His-MBP-linker-LbCpf1 as a model substrate, we show that both types of linkers could be digested by lysostaphin, and the digestion efficiency improved with increasing linker length. The enzyme LbCpf1 retained full activity after tag removal. We further demonstrated that the proteolytic activity of lysostaphin could be well maintained under different environmental conditions and in the presence of a series of chemical reagents at various concentrations that are frequently used in protein purification and stabilization. In addition, such a digestion strategy could also be applied to remove the SUMO domain linked to LwCas13a via an octaglycine linker. This study extends the applications of lysostaphin beyond an antimicrobial reagent and demonstrates its potential as a novel, efficient, and robust protease for protein engineering.


Assuntos
Lisostafina , Peptídeo Hidrolases , Lisostafina/química , Lisostafina/metabolismo , Peptidoglicano/química , Peptidoglicano/metabolismo , Glicina , Parede Celular/metabolismo
17.
J Alzheimers Dis ; 93(1): 169-178, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36970911

RESUMO

BACKGROUND: Olfactory dysfunction appears prior to cognitive decline, and thus it has been suggested to be an early predictor of Alzheimer's disease. However, it is currently not known whether and how olfactory threshold test could serve as a quick screening tool for cognitive impairment. OBJECTIVE: To define olfactory threshold test for screening cognitive impairment in two independent cohorts. METHODS: The participants are comprised of two cohorts in China, 1,139 inpatients with type 2 diabetes mellitus (T2DM, Discovery cohort) and 1,236 community-dwelling elderly (Validation cohort). Olfactory and cognitive functions were evaluated by Connecticut Chemosensory Clinical Research Center test and Mini-Mental State Examination (MMSE), respectively. Regression analyses and receiver operating characteristic (ROC) analyses were carried out to determine the relation and discriminative performance of the olfactory threshold score (OTS) regarding identification of cognition impairment. RESULTS: Regression analysis showed that olfactory deficit (reducing OTS) was correlated with cognitive impairment (reducing MMSE score) in two cohorts. ROC analysis revealed that the OTS could distinguish cognitive impairment from cognitively normal individuals, with mean area under the curve values of 0.71 (0.67, 0.74) and 0.63 (0.60, 0.66), respectively, but it failed to discriminate dementia from mild cognitive impairment. The cut-off point of 3 showed the highest validity for the screening, with the diagnostic accuracy of 73.3% and 69.5%. CONCLUSION: Reducing OTS is associated with cognitive impairment in T2DM patients and the community-dwelling elderly. Therefore, olfactory threshold test may be used as a readily accessible screening tool for cognitive impairment.


Assuntos
Doença de Alzheimer , Transtornos Cognitivos , Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Humanos , Idoso , Diabetes Mellitus Tipo 2/complicações , Testes Neuropsicológicos , Disfunção Cognitiva/psicologia , Doença de Alzheimer/psicologia , Transtornos Cognitivos/diagnóstico , Curva ROC , Programas de Rastreamento
18.
J Chem Neuroanat ; 129: 102251, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36796734

RESUMO

TRIM27 expression was increased in the Parkinson's disease (PD), and knockdown of TRIM27 in PC12 cells significantly inhibited cell apoptosis, indicating that downregulation of TRIM27 exerts a neuroprotective effect. Herein, we investigated TRIM27 role in hypoxic-ischemic encephalopathy (HIE) and the underlying mechanisms. HIE models were constructed in newborn rats using hypoxic ischemic (HI) treatment and PC-12/BV2 cells with oxygen glucose deprivation (OGD), respectively. The results demonstrated that TRIM27 expression was increased in the brain tissues of HIE rats and OGD-treated PC-12/BV2 cells. Downregulation of TRIM27 reduced the brain infarct volume, inflammatory factor levels and brain injury, as well as decreased the number of M1 subtype of microglia cells while increased the number of M2 microglia cells. Moreover, deletion of TRIM27 expression inhibited the expression of p-STAT3, p-NF-κB and HMGB1 in vivo and in vitro. In addition, overexpression of HMGB1 impaired the effects of TRIM27 downregulation on improving OGD-induced cell viability, inhibiting inflammatory reactions and microglia activation. Collectively, this study revealed that TRIM27 was overexpressed in HIE, and downregulation of TRIM27 could alleviate HI-induced brain injury through repressing inflammation and microglia cell activation via the STAT3/HMGB1 axis.


Assuntos
Hipóxia-Isquemia Encefálica , Microglia , Proteínas com Motivo Tripartido , Animais , Ratos , Lesões Encefálicas/metabolismo , Regulação para Baixo , Proteína HMGB1/metabolismo , Proteína HMGB1/farmacologia , Hipóxia-Isquemia Encefálica/genética , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/patologia , Inflamação/genética , Inflamação/metabolismo , Microglia/metabolismo , Oxigênio/metabolismo , Transdução de Sinais , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Proteínas com Motivo Tripartido/genética , Proteínas com Motivo Tripartido/metabolismo
19.
EBioMedicine ; 88: 104432, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36634566

RESUMO

BACKGROUND: Mitochondrial dysfunction is a hallmark of cancer. However, it is unclear whether it is a cause of cancer. This two-sample Mendelian randomization (MR) analyses, uses genetic instruments to proxy the exposure of mitochondrial dysfunction and cancer summary statistics as outcomes, allowing for causal inferences. METHODS: Summary statistics from 18 common cancers (2107-491,974 participants), gene expression, DNA methylation and protein expression quantitative trait loci (eQTL, mQTL and pQTL, respectively, 1000-31,684 participants) on individuals of European ancestry, were included. Genetic variants located within or close to the 1136 mitochondrial-related genes (in cis) and robustly associated with the mitochondrial molecular alterations were used as instrumental variables, and their causal associations with cancers were examined using summary-data-based MR (SMR) analyses. An additional five MR methods were used as sensitivity analyses to confirm the casual associations. A Bayesian test for colocalization between mitochondrial molecular QTLs and cancer risk loci was performed to provide insights into the potential regulatory mechanisms of risk variants on cancers. FINDINGS: We identified potential causal relationships between mitochondrial-related genes and breast, prostate, gastric, lung cancer and melanoma by primary SMR analyses. The sensitivity and the colocalization analyses further refined four genes that have causal effects on three types of cancer. We found strong evidence of positive association of FDPS expression level with breast cancer risk (OR per SD, 0.66; 95% CI, 0.49-0.83; P = 9.77 × 10-7), NSUN4 expression level with both breast cancer risk (OR per SD, 1.05; 95% CI, 1.03-1.07; P = 5.24 × 10-6) and prostate cancer risk (OR per SD, 1.06; 95% CI, 1.03-1.09; P = 1.01 × 10-5), NSUN4 methylation level with both breast and prostate cancer risk, and VARS2 methylation level with lung cancer risk. INTERPRETATIONS: This data-driven MR study demonstrated the causal role of mitochondrial dysfunction in multiple cancers. Furthermore, this study identified candidate genes that can be the targets of potential pharmacological agents for cancer prevention. FUNDING: This work was supported by Styrelsen för Allmänna Sjukhusets i Malmö Stiftelse för bekämpande av cancer (20211025).


Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Neoplasias da Próstata , Masculino , Humanos , Análise da Randomização Mendeliana/métodos , Teorema de Bayes , Estudo de Associação Genômica Ampla/métodos , Neoplasias Pulmonares/genética , Neoplasias da Mama/genética , Neoplasias da Próstata/genética , Polimorfismo de Nucleotídeo Único , Antígenos HLA , Valina-tRNA Ligase/genética , Metiltransferases/genética
20.
Adv Mater ; 35(39): e2209876, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36639855

RESUMO

The energy efficiency of metal-air batteries and water-splitting techniques is severely constrained by multiple electronic transfers in the heterogenous oxygen evolution reaction (OER), and the high overpotential induced by the sluggish kinetics has become an uppermost scientific challenge. Numerous attempts are devoted to enabling high activity, selectivity, and stability via tailoring the surface physicochemical properties of nanocatalysts. Lattice-strain engineering as a cutting-edge method for tuning the electronic and geometric configuration of metal sites plays a pivotal role in regulating the interaction of catalytic surfaces with adsorbate molecules. By defining the d-band center as a descriptor of the structure-activity relationship, the individual contribution of strain effects within state-of-the-art electrocatalysts can be systematically elucidated in the OER optimization mechanism. In this review, the fundamentals of the OER and the advancements of strain-catalysts are showcased and the innovative trigger strategies are enumerated, with particular emphasis on the feedback mechanism between the precise regulation of lattice-strain and optimal activity. Subsequently, the modulation of electrocatalysts with various attributes is categorized and the impediments encountered in the practicalization of strained effect are discussed, ending with an outlook on future research directions for this burgeoning field.

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